Basic Concepts of Ayurvedic Pharmacology

BASIC CONCEPTS OF AYURVEDIC PHARMACOLOGY

Dr. K. NISHTESWAR M.D. (Ayu.), Ph.D., D.A.F.E., Professor & HOD, Dept. of Dravyaguna, Dr. N.R.S. Govt. Ayurvedic College, Vijayawada – 520 002.

Chowkamba Sanskrit Series Office, Varanasi. 2007

Basic concepts of Ayurvedic pharmacology

1

DEDICATION

My beloved father

Dr. K. S. Sharma (Peruru Sharma)

Basic concepts of Ayurvedic pharmacology

2

PREFACE Herbs occupy the important place in the Ayurvedic Materia Medica and therapeutics. Though the drugs that are employed in the management of various diseases include vegetable, animal and mineral in origin, the polyherbal formulations out number the mineral and other metallic preparations. The modern scientists of phytochemistry have identified the following important pharmacologically active principles in medicinal plants viz. a. Alkaloids (Basic substances containing cyclic nitrogen, which are insoluble in water but combine with acids to form water soluble salts) b. Glycosides (Ether like combinations of sugars with other organic structures) c. Glucosides (Yields glucose on acid hydrolysis) d. Oils (Fixed oils, volatile oils and mineral oil) e. Resins (insoluble in water and soluble in alcohol) f. Oleoresins (mixtures of volatile oils and resins) g. Gums (secretory products of plants and are dispersible in water) h. Tannins (Non-nitrogenous plants constituents and precipitate proteins of cells) i. Antibacterial substances fungi and moulds. In the current modern therapeutics the majority of the drugs that are used belong to synthetic in nature. In the modern pharmacology the drug action is quite often correlated with its chemical structure or active principle. But in Ayurvedic pharmacology the drug action is attributed to certain principles/attributes Basic concepts of Ayurvedic pharmacology

3

namely Rasa, Guna, Virya, Vipaka and Prabhava of the active principles of the drug. Rasa or taste of the drug indicates the general behaviour or effect of the drug on bodily or cellular components like Dosha (Vata, Pitta, Kapha), Dhatus (seven types of tissue components), Mala (metabolic debris), Srotas (channels/vessels) and Agni (energy useful to carryout digestion and metabolism of foods & drugs). In the modern pharmacology the modus operandi of the drug is explained through its drug molecule whereas Ayurveda attributes the mode of action of the drug to the five principles (Rasapanchaka). Majority of the times these Gunas (attributes) may not be measurable but inferred through their pharmacological actions. The study of the biological and therapeutic effects of the drugs (what drug does to the body) are explained by these principles which can be identified as pharmacodynamic

principles

of

Ayurvedic

pharmacology.

These

pharmacodynamic principles also influence the pharmaco-kinetics (study of the absorption, metabolism and excretion of drugs and their relationship to the pharmacological response) of the drugs. Routes of drug administration play an important role in the elucidation of drug action. A drug may exert different effects when given by different routes. Thus, oral magnesium sulphate acts as saline purgative. When injected, it is a depressant of central nervous system and acts as an anti-convulsant. On the other hand, hypertonic magnesium sulfate, given as a retention enema, can be used to reduce intracranial tension. Madanaphala when given orally acts as emetic and if administered with Vasti Dravays (ingredients of enema) facilitates for its quicker transportation in the colon by its Urdwabhagahara property and acts as a synergistic for toning up the nervous system or relieving intracranial tension.

Basic concepts of Ayurvedic pharmacology

4

Absorption &Bio-availability of a drug: The route of administration largely determines the latent period between administration and onset of action. Poor absorption of the drug, inactivation in the gut or degradation of the drug during the first passage through the liver can be prevented by administration of Anupanas like honey, pepper, betel leaf juice etc. The particle size of the drug also affects the absorption. Fine powders of the herb quickly get absorbed than coarse particled Churna. Metals in Bhasma (incinerated fine powder) form absorb quickly than coarse powder of metals or minerals. Acid drugs (Amalaki, Nimbu, Amlavetasa etc.) are rapidly absorbed from the stomach. Basic drugs (containing Ksharas) are not absorbed until they reach alkaline environment of the small intestine (Eg. Apamarga, Aswagandha, Sourjakshara, Shank Bhasma etc.) The alakaline environment, in which the major component of the drug exists in an unionised form, facilitates its absorption.

Biopharmaceutics: The study of the influence of formulation on the therapeutic activity of drugs is known as “Biopharmaceutics” and Ayurveda dealt the subject under Panchavidha Kashaya Kalpana i.e., Swasa (fresh juice), Kalka (pounded fresh drug), Kashaya (decoction), Phanta (hot infusion – processed in boiling water) and Hima (cold infusion). The juice of the drug administered having Guruguna (Heaviness) may absorb slowly when compared to the decoction or hot infusion. A faulty formulation process can render a useful drug totally useless therapeutically. A drug having volatile oil / substances processed by Kwatha Kalpana (process of decoction) may loose its major portion of volatile active principles resulting in poor therapeutic response. The drugs that are absorbed in lipid media are suggested to be processed in oil or ghee medium (Eg. Aswagandha). The active principles Basic concepts of Ayurvedic pharmacology

5

soluble in alcohol are available by Asava Sandhana Kalpana but not by Arista Sandhana Kalpana. It is evident that the various Kalpanas (pharmaceutical procedures) were evolved in the light of principles of biopharmaceutics.

Biological lag: The time between the administration of a drug and the development of response is known as the biological lag. Rasoushadhis (mercurial preparation) show a quicker response with less biological lag when compared to herbal formulations.

Bioavailability of drugs: Bio-availability of a drug (availability of biologically active drug) is defined as the amount or percentage of drug that is absorbed from a given dosage form and reaches the systemic circulation following non-vascular administration. When the drug is given I.V., the bio-availability is 100%. This may not be so after oral administration. Acharyas of Ayurveda preached and practiced the oral route of administration for majority of drugs. ‘Anupana’ (substance administered either with the drug or after its administration) facilitates for better absorption of the drug and helps in achieving higher percentage of bio-availability of the drug. 1. Drugs are metabolised by the enzymes. 2. Drugs could change spontaneously into other substance without intervention of enzymes. 3. Drug could be excreted unchanged.

Basic concepts of Ayurvedic pharmacology

6

The alteration of drug’s form and modification of action are well elucidated in Ayurveda in terms of Pratyayarbadhata i.e. Samana and Vichitra Pratyayarabdhata. It may be interpreted that Samana Pratyayarbdhi Dravya may be excreted unchanged while Vichitra Pratyyarabdha Dravya may change into other substances. A careful review of principles of Ayurvedic physiology and pharmacology indicates that Ahara (food substances) and Oushadha (drugs) Dravyas undergo digestion and metabolism synthesises nutritive and active principles along with Kitta formation. The substances like Mutra, Purisha, Sweda are the bi-products of drug metabolism and drug metabolites are excreted through them. The metabolism of drug usually tends to make the less polar, lipid soluble substances (Guru Guna Dravyas) as more polar and water soluble (Laghu) thus facilitating their excretion by kidneys. If a drug is already highly polar and water soluble, then it may not get metabolised and may get excreted as such. Excretion of each and every herb was not studied and reported so far. The important channels of drug excretion are 1. Kidneys 2. Lungs 3. Skin 4. Bile 5. Intestines 6. Milk and 7. Saliva.

Basic concepts of Ayurvedic pharmacology

7

Some fraction of the administered drug disappears (eliminated) from the body and is reflected in the rate of lowering of its plasma concentration (plasma half-life or biological half life). It is very difficult to calculate biological half-life for herbs as the plant contains many active principles and research to assess the concentration of the particular active principle by analysing blood/plasma has not been so far developed. To study the total pharmaco-kinetics of the herb one has to administer it with radioisotopes and plot the journey of the drug which may facilitate also to identify the route of excretion of the drug.

Site of Drug Action: The site of drug action (Adhikarana) and mechanism of drug action (Dravya Prabhava & Guna Prabhava), are the two most fundamental and yet most complex problems in pharmacodynamics. Generalising about the site of drug action (Dosha-Dhatu-Mala-AgniSutas) is easy, but the precise determination of specific site and the mechanism of action of the drug is difficult and often impossible.

A drug may act 

at the point of application (Nipata)



during transportation in the body (Adhivasa)



by reflex effects through nerves



by reaching a definite concentration in a particular tissue. Drugs that act only at the site of application are said to have local or

topical action (through Nipata by Rasa & virya) while those that act after

Basic concepts of Ayurvedic pharmacology

8

absorption are said to have a systemic or general actions (through Nishtakarma & Adhivasa by Vipaka & Virya) Modern pharmacology attributes the activity of a drug to its chemical structure and Ayurveda explains it by the drug’s Panchabhautic configuration and the profile of Panchabhautic ratio is inferred with the general principles like Rasa, Guna, Virya and Vipaka. The ability of a drug to get bound to a receptor is termed as the affinity of the drug for the receptor. The ability of the drug to elicit a pharmacological response after its interaction with the receptor is termed as the intrinsic activity of the drug or efficacy of the drug. A drug which initiates a pharmacological action after combining with the receptors is termed as an agonist. Drugs which bind to the receptors but are not capable of eliciting a pharmacological response are termed as antagonists. An antagonist, therefore, has the affinity as the agonist for the receptor but its intrinsic activity is poor. Facilitation of a pharmacological response by the concomitant use of two or more drugs is called synergism. This combination usually results in a total effect greater than the sum of their independent actions. By combining Tulya Virya (similar potency) drugs the formulation acts by synergism. The phenomenon of opposing actions of two drugs on the same physiological system is termed as drug antagonism. The best example is administration of Viruddha (opposite) Virya drugs. Eg. The combination of Rasna (Vathara drug) with Jambu (Vatakara drug)

Basic concepts of Ayurvedic pharmacology

9

Though the term potentiation is not acceptable to modern pharmacology Charaka has explicitly promulgated the concept of potentiation of drug efficacy by triturating the drug with its own juice (Swarasa Bhavana). Drug incompatability is similar to the concept of Virudhatwa described in Ayurveda. Ayurveda has also recorded adverse drug reaction with certain herbs like Bhallataka (marking nut) etc. It was my preveilage to work under late Prof. Shivcharan Dhyani, H.O.D. Dept. of Dravyaguna, I.P.G.T & R, Gujarat Ayurved University, Jamnagar, who was a fountain source of inspiration and rendered his ablest guidance during my Post-Graduate studies. The research work carried out under his guidance on the concept of Virya was published already in some of the standard Ayurvedic Journals. For the benefit of students of Ayurveda and academicians, I have reproduced some of the salient concepts of Ayurvedic Pharmacology along with the summary of Research Studies carried out by me on Virya – one of the fundamental principles of Drug action. I believe the readers will find the study of this book rewarding and satisfying. I specially acknowledge M/S Chowkhamba Sanskrit Series, Varanasi for publishing this work.

Date: 22-5-2007 K. NISHTESWAR

Basic concepts of Ayurvedic pharmacology 10

CONTENTS

PREFACE INTRODUCTION 1. PRINCIPLES OF DRUG ACTION 2. ESSENTIAL COMPONENTS OF DRUG EVALUATION 3. VIRYA – AN IMPORTANT ATTRIBUTE OF DRUG ACTION 4. EXPERIMENTAL STUDIES BIBLIOGRAPHY

Basic concepts of Ayurvedic pharmacology 11

INTRODUCTION The subject of usage of herbs and herbo-mineral drugs is as old as disease. Illness has been human beings heritage from the beginning of the existence of life and the search for remedies to combat it is perhaps is equally old. The herbs and other things were in use as medicine to a limited extent from the very Vedic period. Over and above these medicinal plants, metals like gold, lead, tin, copper etc. were known to the Vedic Rishis, but there is no evidence to show that they were put to any medicinal use in those days. Their medicinal use receives more attention during the Samhita period. Due to great influence of Atharvan more importance was attributed to divine Basic concepts of Ayurvedic pharmacology 12

therapy (Daivavyapasraya medicine) viz. incantations, gems or magical stones, herbal amulets and sacred water etc. This was just an incipient gleam of knowledge of therapeutics. The object of such reference to the drugs of the Vedic times is to show that there was no definite theory to explain the actions of drugs in those days and even if there was one, we have no means of knowing it. Gradually, the floating ideas of Vedic times received more thinking and more criticism till they were put together to form a comprehensive theory regarding the pharmacology of drugs. In this course of development, the fundamentals must have faced great controversies and after long scientific discussions only, they could have attained their stability as we find such illustrations in Charaka and Sushruta Samhitas. On account of incessant intellectual activities and numerous observations by several workers, the number of drugs enormously increased during the Samhita period. Not only this but the old empiricism had disappeared, giving place to a definite theory, known as a theory of Rasa, Guna, Veerya, Vipaka and Prabhava. With this effect the herbal therapy went on progressing as a rational (Yuktivyapasraya) school of medicine. Ayurveda is mainly concerned with prescribing drugs to balance the vitiated doshas. It’s pathology is concerned with doshas, dhatus and malas. So, any action of the drug is to be explained only on this basis.

Modern Pharmacology being interested in studying the actions of the drug on different systems or parts of the body describes all drugs on the basis of Karma, they perform. In Ayurveda, in relation to pharmaco dynamics, the Basic concepts of Ayurvedic pharmacology 13

properties of drugs have been described in terms of Rasa, Vipaka, Guna, Virya and Prabhava. Drayva i.e., substance (food or drug) acts by its innate qualities (Gunas) such as Rasa, Guna, Virya, Vipaka and Prabhava or through its own Prabhava. Panchamaha Bhutas act as contributing factors for the formation of a dravya as well as its Gunas. The elementary substances (Panchamula Bhutas) with which every substance is constituted are the Karana or the cause and hence they are called as Karana Dravyas. Whereas Rasa, Guna, Virya, Vipaka and Prabhava of the substances which arise out of the permutations & combinations of the 5 elementary substances in various modes and patterns are really the effects or Karyas. Substances arise out of the various modes of permutations and combinations of the five elementary substances are described as Karya Dravyas. The properties which exist in the causative factors (Panchamaha Bhutas) are present in the resultant factors (Karya Dravyas). These properties become actualized in the effect or Karya; which are described in terms of Rasa, Guna, Virya, Vipaka and Prabhava. Rasadi Panchaka are the modes of Gunas of Panchamaha Bhutas and stated in terms of recent trends in the modern physics – “The initial state of a system wholly determines its subsequent states.” The Dravyas arise on the substrate of Prithvi. A review about the scientific implications of these principles (Rasapanchaka) of drug action is mandatory to understand the rationality of modus operandi of Ayurvedic drugs. Basic concepts of Ayurvedic pharmacology 14

RASA It is an important quality manifested at the level of tongue and is the only principle or quality which can be directly perceivable. The Rasa or taste which is cognized first (by impact with the tongue) is considered as Rasa (Primary taste) and the Rasas which are less apparent or cognizable are called Anurasas (Secondary Taste). Scholar of Dravya Guna of Modern Ayurveda namely Acharya Priya Vrat Sharma has discussed concept of Rasa basing on the Physico-Chemical constitution of substances as follows: Madhura

-

Sugar, Fat and Amino Acids

Amla

-

Acids

Lavana

-

Salts

Katu

-

Essential Oils, Phenols etc.,

Tikta

-

Certain Alkaloids and Glycosides

Kashaya

-

Tannins

According to his hypothesis “carbohydrates and proteins are present in Madhua Rasa Dravyas. All the Amla Rasa Dravyas have shown Acidic Reaction and all the Dravyas in Lavana Varga are containing Sodium Chloride. All the Dravyas of Katu Varga are containing essential oil while 50% of Katu Dravyas contain alkaloids or glycoside or phenols. All the Tikta Drayvas contain alkaloids and only 10% of Dravyas contain Glycosides. Many of the Kashaya Rasa Dravyas contain tannin”. Professor Dwarakanath has attempted to evolve a method known as “Taste Threshold” for quantitative determination of Rasa in a given substance. The test is meant for Basic concepts of Ayurvedic pharmacology 15

evaluating the intensity or degree of the taste which finally depends on the tongue only and not with any other laboratory instruments. The taste perception and taste sensibility are complex Bio-Physical and Psychological events and translation of Rasa cannot be exactly evaluated without the help of tongue.

Rasa & Guna Panchabhoutic combination and primary physical qualities or Gunas of different Rasas are mentioned in the Ayurvedic Classics. Though it appears that Gunas are intimately related to Rasas it is a fact that both are separate principles co-existent in the Dravya. This statement reflects that Rasa acts by its own Prabhava independent of the Gunas attributed to it. “Of the six Rasas Katu, Amla and Lavana possess consecutively Ushna Virya in progressively increasing degrees. Likewise, Tikta, Kashaya and Madhura Rasas possess consecutively Sita Virya in progressively increasing order”. According to this reference the six Rasas finally exercise their general actions by two principles or gunas namely Sita & Ushna and specific action on malas by another pair of Gunas namely Ruksha (Badda Mala – Binding of waste products) and Snigdha (Srishtamaltwa – Proper elimination of waste products). Another pair of Gunas namely Guru and Laghu are attributed to six Rasas. Lavana, Kshaya and Madhura Rasas possess Guru Gunas in progressively increasing degree (relatively superior) and similarly Amla, Katu, Tikta relatively attributed with Laghu Guna. Brimhana and Langhana are the actions of Guru and Laghu Gunas and the specific action of Rasas on Dhatus can be interpreted with Guru and Laghu Gunas. In a nut shell, the Shad Rasas (six tastes) are bestowed with the ability to participate in Shad Upakarmas (six therapeutic measures) with the Basic concepts of Ayurvedic pharmacology 16

help of six Gunas namely Ushna-Sheeta, Sringdha-Ruksha and Guru-Laghu.

Gunas

Upakrama

Rasa

Ushna

Swedana

Katu, Amla, Lavana

Sheeta

Stambhana

Tikta Kashaya, Madhura

Snigdha

Snehana

Lavana, Amla, Madhura

Ruksha

Rukshana

Tikta, Katu, Kashaya

Guru

Brimhana

Lavana, Kashaya, Madhura

Laghu

Langhana

Amla, Katu, Tikta

The above table clearly indicates that Dravya exercises its action through Gunas only and the individual Rasas of Dravyas help to infer the inherent Gunas of respective Dravyas. Virya-Vipaka: Next to the concept of Rasa, Acharyas have the concepts of Virya and Vipaka which are directly related to Bio-Physical and Bio-Chemical events of food substances and drugs. Ahara or food and Oushadha or medicinal substances are subjected to physiochemical reactions or Pakas at Gastrointestinal and tissue levels. Charaka defined that Virya as the power that performs work. All actions takes place only because of Virya and there is no action which is not due to Virya. According to this definition the principles like Rasa, Gurvadi Guna, Vipaka and Prabhava which could be causative factor for the action is generally identified as Virya. But, Sushruta, Vagbhata and their followers did not agree with the views of Charaka and applied the term Virya to the eight primary qualities of elementary substances viz., Mridu-Teekshana, Guru Laghu, Snigdha-Ruksha, Ushna-Sita. Commenting on the concept of Basic concepts of Ayurvedic pharmacology 17

Dwividha Viryas Hemadri quotes “Although the eight Gunas of Dravyas become actualized in the process of their Paka by kayagni, they (the Gunas eight or twenty) are ultimately transformed to Ushna and Sita due to the greater exaltation of these two Gunas (i.e., Ushna and Sheeta) which obscure or supercede the other Gunas.”

Classification of twenty Gunas Anna or Shoma or Sita

Prana or Agni or Ushna

Virya or Potential Energy

Virya or Kinetic Energy

Guru

Laghu

Shita

Ushna

Snigdha

Ruksha

Manda

Tikshna

Sthira

Sara

Kathina

Mrudu

Pichchila

Vishada

Shlakshana

Khara

Sthula

Sukshma

Sandra

Drava

Eight gunas with Virya status Anna or Shoma or Sita Virya

Prana or Agni or Ushna

or Potential Energy

Virya or Kinetic Energy

Guru

Laghu

Snigdha

Ruksha

Shita

Ushna

Mridu

Tikshna

Basic concepts of Ayurvedic pharmacology 18

Shivadas classified Virya as Sahaja (natural) and Kritrima (artificial) Dravya

Rasa

Guna

Vipaka

Virya

Milk

Madhura

Guru

Madhura

Sita

Curd

Amla

Laghu

Amla

Ushna

Sali

Madhura

Guru

Madhura

Sita

Laja

Madhura

Laghu

Katu or Amla Ushna

Viryas of Rasas: Rasa

Virya

Katu, Amla, Lavana

Ushna

Tikta, Kashaya, Madhura

Sita

Properties of different Viryas Name of the Virya Ushna

Action/Effect produced Bhrama (giddiness) Trishna (Thirst) Glani (Bodily fatigue or exhaustion) Sweda (Sweating) Daha (Burning sensation) Asupakita (Accelerates digestion or biochemical reaction) Vata-Kaphahara

Sita

Hladana (cheerfulness or pleasure of mind) Jivana (Surtains life) Stambhana (Binding or preventing secretions) Raktapitta Prasadana (cleanses Rakta & Pitta)

Basic concepts of Ayurvedic pharmacology 19

Kledana Vishyandana Guru

Brimhana (increases the body weight) Vatahara

Laghu

Langhana (reduces the body weight) Kaphahara

Snigdha

Snehana Kledana Balya Varnya Brhimhana Vajeekarana Rasa

Ruksha

Soshana Sangrahana Peedana Ropana

Mrudu

Pitta Prasamana Raktamamsa Prasadana Slathana

Tikshna

Sleshmahara Samgrahana Sravana Dharana Avachushana Sodhana

Assessment of Rasa, Vipaka and Virya: Basic concepts of Ayurvedic pharmacology 20

The Rasa (taste) of a Dravya (substance) is felt at the commencement only i.e. when the Dravya comes in contact with the tongue (Nipata) and Vipaka is inferred only after perceiving the final effects of digestion and metabolism is produced (Karma Nishta) while Virya is identified throughout the stay of the substance in the body (Adhivasa) and also at the beginning through the contact with the tongue. (Nipata)

Sushruta suggests the following assessment criteria for eight Virya: Name of the Virya

Method of assessment

Mridhu, Sheeta, Ushna

Sparshagrahya (Tacticle Perception)

Pichchila, Visada

Chakshu Sparshagraha (Visual & Tactile Perception)

Snigdha, Ruksha, Tikshna

Chakshu grahya (Visual perception)

Tikshna

Mukhadukhodpana (Irritating the buccal mucosa)

Though Sushruta considers that Virya by Pratyaksha Pramana, Charaka opines that Virya of the dravya is identified through inference (Anumana) according to its stay in the body while Virya of certain drug can be assessed by Pratyaksha Pramana (direct perception) after its contact with the tongue. Hemadri while commenting on the evaluation of Guna attributed specific actions to certain Gunas which are given Virya status viz., Guru

-

Brimhana

Laghu

-

Langhana

Sita

-

Sthambhana

Ushna

-

Swedana

Snigdha

-

Kledana

Basic concepts of Ayurvedic pharmacology 21

Ruksha

-

Soshana

Mridu

-

Slathana

Tikshna

-

Sodhana

An attempt to evaluate the attributed Karmas at biological level either in animal or by human experiments may provide scientificity to the concept of Virya. Professor Dwarakanath explains the concept of Virya in the light of Modern definition of energy “the energy of a body is its capacity for doing work; the measure of energy is work; when chemical changes take place energy is liberated or absorbed; usually as heat but occasionally as light, electricity or work. A reaction which liberates heat energy is said to be exothermic (Ushna Virya) and one which absorbes heat energy is said to be endothermic (Seeta Virya). Energy may be kinetic or potential. The energy locked up in substances especially food is known as chemical potential energy (Seeta Virya). The energy that is released for work by oxidation is known as kinetic energy (Ushna Virya). For transformation of energy from one form to another Paka Karma (Vipaka) in Dhatus or tissues is highly essential. The breakdown reactions (Catabolic) and reactions leading to synthesis (Anabolic), involving the release and locking up of energy respectively are together known as Paka Bhedas. From the above discussion it can be concluded that various energy forms are the modalities of Virya and reactions for the release or conservation of energy are the various forms of Vipaka. Gunas or physical Basic concepts of Ayurvedic pharmacology 22

qualities or physical properties of substances are modes (or different manifestations) of Virya or energy. All the twenty Gunas comprising ten each of the opposites can be classified broadly under two Virya modes viz., Ushna and Sheeta corresponding to kinetic and potential energies respectively. Out of twenty Gunas, considerable significance has been attached to eight Gunas otherwise known as Asta Viryas as they are deemed to be effective in the performance of actions.

Vipaka: The Rasas of substances ingested being acted upon by Jatharagni are changed to different other tastes after attaining Pakva. It is this transformation of Rasas that is spoken of as Vipaka. A substance which is Madhura (sweet) in taste and Vipaka, is Sita Virya, that which is Amla Rasa and Vipaka, is Ushna in Virya. Similarly, that which is Katu in Rasa and Vipaka is Ushna in Virya. Various Vipakas represent highly specialized reaction to synthesise ultimate metabolic products. Regarding the number of Vipakas different scholars held different views. Some hold that there are as many Vipakas as there are Rasas. 

According to Charaka Vipakas are three viz., Madhura, Amla and Katu.



According to Sushruta, Vipakas are only two viz., Madhua and Katu.



Parashara has advanced another view that Tikta and Kashaya Rasas undergo Madhura Paka.



In the view of some of the authorities quoted by Sushruta, there are as many Vipakas as there are Rasas.



In the opinion of Ayurveda Sutra – substances that possess Katu Rasa may undergo Lavana Paka, Tikta Rasa may undergo Madhura Vipaka Basic concepts of Ayurvedic pharmacology 23

and Kashaya Rasa may undergo Amla Vipaka. Some interpret Vipakas as the specific mode of Pancha Bhoutic structure of the elemental units of the ultimate metabolic products. According to Hemadri “that evokes taste perception is Rasa and all the rest are Gunas. Particular or distinct Visishta Rasa or taste that occur as the result of Kayagnipaka is Vipaka and generated Guna at this stage is known as Virya”. The substances are identified by two varieties of tastes i.e., Rasa (general) of a Dravya at tongue level (Shad Rasas) and Rasa (specific or Visishta) of a Dravya which has undergone Paka and specially named as Vipaka. Rasa and Vipaka are the two forms for the identifying the actions of substances either by direct perception at tongue level (Nipata) and by inference assessed through final action (Nishta Paka). The final action achieved by Dravya continues as long as the bodily contact with engendered Guna or Virya through Vipaka maintains (Adhivasa). The action ceases when Virya (Virya Yukta Dravya i.e., Drug Molecule) is excreted or expelled out of the body. The action attributed to Rasa, Virya and Vipaka are explained in terms of Guna only. Charaka has tried to explain regarding the identification or recognition of these Gunas at various contact points in the body during the journey of the drug such as Gunas identification at tongue level with the help of Rasa (Nipatat) by direct perception and through inference at Dhatu (tissue) level; with the terms such as Vipaka (Nishtapaka) and Virya (Adhivasa)

Basic concepts of Ayurvedic pharmacology 24

Prabhava: Prabhava has been defined as the special property of a substance which produces actions different from and contrary to those ascribed to Rasa, Guna, Virya and Vipaka. The concept of Prabhava appears to be generally resembling the concept of isomerism and isomerides of modern physical compositions and yet exhibit different properties. The chemical composition which largely determines the secondary qualities of a Dravya such as Rasa, Guna, Virya and Vipaka does not determine a chemical compound. The Rasa, Guna, Virya and Vipaka of Danti and Chitraka being apparently identical, the former produces purgation, whereas the latter does not produce this action and the specific purgative action of Danti is attributed to its Prabhava (inexplicable nature). It is easy to evaluate or assess different Karmas (pharmacological actions) of drugs through various experimental models but it is a tough task to evolve objective methodology for demonstration or identification of principles of drug action. Acharyas of Ayurveda clearly mentioned that Gunas are inferred by their Karmas or actions which are perceivable. In order to test the medicinal value of any drug, three methods i.e. (i) Clinical,

(ii) Pharmacological and (iii Experimental are in practice

from a time immemorial. In those days the experimental trial was in rudimentary stage and the clinical evaluation was very common. Now a days, though more stress is being given on animal experimentation. But this does Basic concepts of Ayurvedic pharmacology 25

not help to that extent, in order to declare the utility of a drug, as is confirmed after clinical testings. Moreover, the results obtained in experimental animal are often found to be different to that of human beings. Thus, it becomes evident that the ancient drugs having clear cut indications, ascribed in the texts should not be ignored or accepted only on experimental basis, until they are tested clinically both with active principles (isolates) as well as total drug.

Basic concepts of Ayurvedic pharmacology 26

1. PRINCIPLES OF DRUG ACTION The Ayurvedic Science delineated important three principles (Trisutra) viz., etiology (Hetujnana), symptomatology (Lingjnana) and therapeutics (Oushadhajnana). Etiology includes the immediate and distant cause of diseases. Similarly the symptomatology includes the entire signs and symptoms of diseases and health and the therapeutics include wholesome diet along with the treatment of diseases. Ayurvedic concepts of pharmacology are included under Oushadhajnana.

Correct Application of the drug is essential: The goatherds, shepherds, cowherds and other forest dwellers know the drugs by name and form. No one can know the principles governing correct application of drugs simply by knowing their names and forms. A physician, even ignorant of their forms can be said to be a knower of the essence [of science] if he is acquainted with the principles governing the correct application of drugs, let alone the one who knows drugs in their entirety. One who knows the principals governing their correct application in consonance with the place, time and individual variation, should be regarded as the best physician. Of course, the best physician is he who is well acquainted with the drugs in their entirety. One has to establish the correct identification of drug prior to its collection. Sushruta suggests that the knowledge of identification of herbs can be obtained by contact with cow-herds, herds, hermits, hunters and others who roam in jungles and take root (of plants) as food. A drug not known is likened to poison, weapon, fire and thunderbolt Basic concepts of Ayurvedic pharmacology 27

while the one known, to the nectar. A drug known in respect of its name, form and properties or even if known, improperly administered, leads to bad consequences. Proper application of drugs depends upon their proper knowledge. Unless the physician knows the drugs properly he cannot cure a patient; his prescription would rather kill his patient. The drug unknown, might act as poison which kills after bringing about unconsciousness or as a weapon which kills after piercing through the vital organs, or like fire which kills by causing boils, etc. or as a thunderbolt which kills instantaneously. It is only when a physician knows all the three aspects, viz., name, form and properties of drugs. The physician can treat the patients successfully. Even an acute poison can become an excellent drug if it is properly administered. On the other hand even a drug, if not properly administered, becomes an acute poison. So a wise patient desirous of longevity and health should not accept any medicine prescribed by a physician ignorant of the principles governing its application. Some times, one might escape (death) even when thunderbolt of Indra has fallen on his head, but one can never survive if he takes medicine prescribed by a physician ignorant of the application. To sum up, neither the patient should take medicine prescribed by pseudo-physicians, nor a physician, without being proficient in the principles governing the application of drugs. Only that, which can bring about a cure, is a correct medicine. It is only he who can relieve his patients of their ailments is the best physician. Basic concepts of Ayurvedic pharmacology 28

For the purpose of the Science of medicine, it is necessary to explain the qualities of correct medicine and a good physician. It is only that which possesses the requisite curative values is to be treated as a correct medicine. As regards physician, he should first of all know the principles underlying the correct application of medicines. Unless he knows it, he will not be able to relieve his patients of their ailments. Even if per chance, medicines selected by him at random succeed in alleviating ailments, the credit is considered as accidental one.

Classification of Dravya: Akasa etc., (Prithvi, Ap, Tejas, Vayu and Akasa), soul, mind, time and space constitute matter. Matter having sense organs is sentient while the one devoid of them is insentient. Chakrapani Dutta interprets that “This definition applies also to the vegetable kingdom; that is to say the vegetable kingdom is also sentient. Many examples can be cited to prove this. The Suryabhakta (Helianthms annus Linn.) moves according to the movement of the sun. The Lavali (Gicea acida Merrill) gets fruits just on hearing the sound of the thunder. The Bijapuraka (Citrus medica Linn.) tree produces fruits only by the smell of the fat of jackals etc., similarly Amra (Mangifera indica Linn.) trees when irrigated with the fat of fish, produces fruits in plenty. Ashoka tree (Saraca indica Linn.) hit with the sole of the feet of a lady begets flowers. The above example clearly indicates the presence of the various sense organs in the vegetable kingdom as well.

This is also attested from scriptures. “If a

Brahmin does not give blessings in response to salutations, he is born in a cemetery as a tree surrounded by vultures and Kankas.” “Trees, shrubs and other varieties of grass are covered with darkness arising out of their sinful Basic concepts of Ayurvedic pharmacology 29

acts but they all have consciousness full of happiness and miseries. The extent of creation beginning with Brahma is up to vegetable kingdom.” Thus, the members of the vegetable kingdom have got life as well as consciousness. So they belong to category of sentient matter”. Vedic lorwe clearly indicated that plants do have life and modern scientists like Jagadish Chandra Bose have tried to revalidate these concepts through scientific experiments. Drugs are of three categories, some alleviate Doshas, some vitiate Dhatus and some are good for the maintenance of positive health. This three-fold classification of drugs also includes other type of drugs which are responsible for elimination and suppression of Doshas. Elixirs and aphrodisiac drugs come under the third category which are responsible for the maintenance of positive health. The use of the term “Dosha” and “Dhatu” in the first and second category of classification is quite significant. “Doshas” include “Dhatus” and Vice-Versa. So the drugs that are designated as alleviators of the Doshas also alleviate Dhatus. Similarly, the drugs that have been designated as vitiators of the Dhatus do as well vitiate Doshas. The drugs under the third category are those which have potentialities to maintain the positive health. Apparently it also means that the drugs have got potentialities to prevent the diseases. According to another classification, Dravyas are of three kinds viz., those of animal origin, those of vegetable origin and metals including minerals. Different types of honey, products of cow milk, bile, fats of Basic concepts of Ayurvedic pharmacology 30

muscle tissue, marrow, blood, flesh, faeces, urine, skin, semen, bone, ligament, horn, nail, hoof, hair, Lomana, (hair of the body excluding those of the head and face), Rochana (purified Ox bile) - are some of the drugs of animal origin used in medicine. Gold, five Lohas (copper, silver, tin, lead, and iron) along with their byeproducts (different types of bitumen), calcites along with silica, red arsenic, yellow arsenic, gems, salt, red chalk, collyrium – are in brief the metals and minerals used in medicine.

The drugs of vegetable origin are of four types viz.

Vanaspati,

Vaanaspatya, Virudh, and Oshadhi. Vanaspati is the one having fruits only (without flower).

Vaanaspati has flowers as well as fruits.

The drugs

belonging to the class of Virudh are those which spread with branches. Oshadhis are those which die out when their fruits mature. The root, bark, Sara (aqueous extract), secretions, fibre, juice, tender leaves, alkali preparations, latex, fruits, flowers, ashes, oils, thorns, matured leaves, adventitious roots, rhizomes, sprouts are belonging to the group of drugs of vegetable origin. In another classification the drugs are classified according to part used viz., Moolini (Root) and Phalini (fruits).

The Mula (Root), Twak

(bark), Sara (heartwood), Niryasa (Secretions/gums), Nala (fibre), Swarasa (juice), Pallava (tender leaf), Kshara (Alkali), Ksheera (latex), Phala (fruit), Bhasma (Ash), Taila (oil), Kantaka (Thorn), Patra (leaf), Sunga (adventitious roots), Kanda (rhizome), Praroha (sprouts) are the useful parts of the drugs of vegetable origin. Charaka also describes the plant with useful parts like roots Basic concepts of Ayurvedic pharmacology 31

and fruits which are indicated in Panchakarma measures. He further explains about the drugs that are useful for various elimination (sodhana) therapies in Apamarga Tanduliyaka (Dehusked seeds of Apamarga) chapter. Drugs are of two kinds – one variety of drugs is used for internal cleaning (Abhyantara Parimarjana) and the other for external cleaning (Bahi Parimarjana). The drugs related to later category are described under Aragwadhiyam chapter. In the chapter entitled ‘Satvirechana Satashritiyam’ the drugs useful both for internal as well as external cleansing are being explained. In this chapter fifty groups consisting of ten drugs each on the basis of pharmacological actions as well as therapeutic utility are introduced by Charaka which are popularly known as Dasaemani. In total five hundred drugs are listed among fifty groups and the same drug is repeatedly quoted in a number of groups of decoctives. After elaborative descriptions about the drugs of different groups Charaka humbly states that “the description of 500 decoctives (Mahakashaya) is neither too exhaustive nor too brief. Physicians of lower intelligence will, of course, find this list useful enough in the treatment of various diseases but those possessing high intellectual caliber need not confine themselves to this list. Physician may exercise his own imaginative power in finding out other similar drugs as well, according to the principles laid down in Ayurveda and keeping in view the requirements of the patient.

Dravya Pradhanya – (Importance of the substance): Dravya (substance) is the chief (most important) among Rasa (tastes) and others qualities; because all of them (qualities) are residing in it (substance).

Basic concepts of Ayurvedic pharmacology 32

It (substance) is Panchabhutatmaka (composed of, born from the five elements), it has Ksma (Prithvi Bhuta) as its substratum (mass, support), it takes origin from Ambu (Apbhuta), Agni (Tejas Bhuta), Pavana (Vayu Bhuta) and Nabhas (Akasa Bhuta), with their intimate (inseparable) combination making for its formation and specify (of each substance). Its identification/designation is by preponderance (predominance, of the Bhuta present in it).

Nothing is Non – Medicinal There is nothing in this universe, which is non-medicinal, which cannot be made use of for many purposes and by many modes. Origin of substance takes place by combination of Prithvi, Ap, Tejas, Vayu and Akasa. Only predominance of one of them creates distinctions such as this is Parthiva, this is Apya, this is Taijasa, this is Vayavya and this is Akasiya.

Parthiva Dravya Lakshana (Qualities of Parthiva substances) The substance which possesses qualities such as Guru (heaviness), Sthula (bulky), Sthira (stable) and predominant in Gandha (smell) is Parthiva (earthy); it bestows heaviness, stability, compactness and growth.

Apya Dravya Lakshana (Qualities of Apya substances) The substance which possesses qualities such as Drava (liquidity), Sita (cold), Guru (heaviness), Snigdha (unctuousness, moisture, oiliness), Manda (dull), Sandra (thickness, dense) and predominant in Rasa (taste) is Apya (watery); it confers lubrication (moistness), secretion (moisture, production), Kleda (keeping wet), satiation (contentment, satisfaction) and cohesion (binding, holding together). Basic concepts of Ayurvedic pharmacology 33

Agneya Dravya Lakshana (Qualities of Agneya substances) The substance which possesses qualities such as Ruksha (dry), Tikshna (penetrating, sharp), Ushna (hot), Vishada (non-slimy), Sukshma (minute) and predominant in Rupa (appearance, showing, from); it causes burning sensation, lustre, expression of colour and digestion (process of transformation, putrefaction etc.)

Vayaviya Dravya Lakshana – (Qualities of Vayaviya Substances) Vayaviya substance possesses qualities such as Ruksha (dry), Vishada (non-slimy), Laghu (lightness) and predominant in Sparsa (touch tactile sensation), it produces dryness, lightness, transparency, movements (different kinds of activities) and exhaustion.

Nabhasa Dravya Lakshana – (Qualities of Nabhasa Substance) Nabhasa (Akasiya) substance possess qualities such as Sukshma (minuteness), Visada (transparence, clearness), Laghu (lightness) and predominant in Sabda (sound, hearing); it produces cavitation (hollowness) and lightness (weightlessness). Purgative drugs are predominant in qualities of Prithvi and Ap which are heavy and as such move downwards, hence, by inference, purgative is predominant in qualities of down-moving elements eg. Prithvi and Ap; emetic drugs are predominant in qualities of Agni and Vayu which are light and as such move upwards, hence emetic is predominant in qualities of upmoving elements e.g. Agni and Vayu. That acting in both ways in predominant in qualities of both the above two; pacifying drug is predominant in qualities of Akasa; astringent drug is predominant in qualities Basic concepts of Ayurvedic pharmacology 34

of Vayu because of its drying nature; Dipana (stimulating digestive fire) is predominant in qualities of Agni because of its similarity; Lekhana (decreasing body-weight) is predominant in qualities of Vayu and Agni; Brimhana (increasing body-weight) is predominant in qualities of Prithvi and Ap. In this way, action of drugs may be interpreted by inference. Here heaviness and lightness should be taken as governed by specific potency situated in Trivrit, Madana etc. and not in the ordinary sense otherwise fish, floury food, lentils etc. would be purgatives and grey partridge, quail etc. might come into the emetic group; Lekhana – decreasing body-weight, by depleting Kapha and fat. Vayu is pacified by substances composed of Prithvi, Tejas and Ap; Pitta is pacified by those composed of Prithvi, Ap and Vayu while Kapha is pacified by substances composed of Akasa, Tejas and Vayu. (On the contrary), Vayu is increased by substances composed of Akasa and Vayu, substance which is igneous in nature increases Pitta while Kapha is increased by those composed of Prithvi and Ap. In this way, in every substance, the predominance of qualities should be observed and, considering its effect on two or more Doshas, that should be applied in case of aggravated Doshas.

Drug classification according to Rasa (According to Sushruta): Substances in reference to all are enumerated such as Kakolyadi group, milk, ghee, muscle-fat, marrow, Sali and Sastika rice, barley, wheat, blackgram, Sringataka, Kaseruka, Trapusa, Ervaruka, Karkaruka, Alabu, Kalinda, Kataka, Gilodya, Priyala, Pushkarabija, Kashmarya, Madhuka, Basic concepts of Ayurvedic pharmacology 35

Draksha, Kharjura, Rajadana, Tala, Narikela, products of Ikshu (sugarcane), Bala, Atibala, Kapikacchu, Vidari, Payaysa, Gokshura, Kshiramorata, Madhulika, Kushmanda etc. are included in the sweet group. Dadima, Amalaka, Matulunga, Amrataka, Kapittha, Karamarda, Badara, Kola, Prachinamalaka, Tintidika, Koamra, Bhavya, Paravata, Vetraphala, Lakucha, Amlavetasa, Dantasatha, curd, buttermilk, Sura (alcoholic beverage made of barley), vinegar, different types of sour gruel etc. are included in the sour group. Saindhava,

Sauvarchala,

Vida,

Pakya,

Romaka,

Samudraka,

Paktrima, Yavakshara, that obtained from desert, Suvarchika etc. are briefly, the members of the salty group. Pippalyadi, Surasadi, Sigru, Madhusigru, Mulaka, Lasuna, Sumukha, Sitasiva, Kustha, Devadaru, Harenuka, Bakuchiphala, Chanda, Guggulu, Musta, Langali, Sukanasa, Pilu etc. and mostly Salasaradi group come in the pungent group. Aragvadhadi, Guduchyadi, Mandukaparni, sprouts of Vetra, two types of Haridra, Indrayava, Varuna, Vikankata, Saptaparna, two types of Brihati, Sankhini, Dravanti, Trivrit, Kritavedhana, Karkotaka, Karavellaka, Vartaka, Karira, Karavira, Jati, Sankhapushpi, Apamarga, Trayamana, Katuka, Vaijayanti (Tarkari), Suvarchala, Punarnava, Vrischikali, Jyotismati etc. briefly, come in the bitter group. Nyagrodhadi, Ambasthadi, Priyangvadi, Rodhradi, Triphala; fruits of Sallaki, Jambu, Amra, Bakula, Tinduka, Saka and Nyagrodha etc; Basic concepts of Ayurvedic pharmacology 36

Pasanabheda, mostly Salasaradi group, Kuruvaka, Kovidara, Jivanti, Chilli, Palankya, Sunisannaka etc. and Varaka, Mudga etc. are included in the astringent group.

DRUG ACTION It is not that the various drugs and diets act only by virtue of their qualities. In fact they act by virtue of their own nature or qualities or both on a proper occasion, in a given location, in appropriate condition and situations; the effect so produced is considered to be their action (Karma); the factor responsible for the manifestation of the effect is known as Virya; where they act is the Adhisthana (location); when they act is the time, how they act is the Upaya or mode of action; what they accomplish is the achievement or therapeutic effect. (Charaka Smhita) Chkrapani Dutta further explains that some drugs act by virtue of their own nature; e.g. Danti (Baliospermum montanum Muell-Arg.) is purgative and precious stones are antitoxic. Some other drugs act by virtue of their qualities; e.g. fever is cured by drugs having bitter taste and coldness by the heat of the fire. Some other drugs act by virtue of their own nature as well as their qualities; e.g. cow milk boiled with a gold ring is considered to be aphrodisiac – Rcf. Chikitsa2:3:11, by virtue of the very nature of gold as well as its circularity. When errhines are administered they eliminate Doshas from the head – that is their action. The factor like heat which is responsible for this action is Virya (potency) relating either to the drug or its quality. The site where the elimination takes place i.e.is the Adhikarana (location); errhines do not act when administered elsewhere. The spring season or the time when the Basic concepts of Ayurvedic pharmacology 37

head is heavy is the appropriate time or Kala for the administration of this therapy. This therapy is not effective in other seasons or occasions. This therapy is to be administered in accordance with the prescribed procedure. Pradhamana and Avapidana are to be administered while the patient lies on a bed covered with a bed sheet; his head is projected out of the bed and his eyes are closed.

This is Upaya or mode of administration.

By the

administration of this therapy, heaviness and pain etc., of the head are cured. This is Phala or the object of treatment. The modern investigations on the action of drugs are carried out by observing the effects when these are 1. Administrated to living animals – healthy or diseased. 2. Applied on the isolated organs or other tissues of certain animals & also on various infecting organisms. 3. Investigated through radio-activate isotopes and by electron microscope. 4. Also administered to a human being in healthy and in diseased states for therapeutic purpose. While explaining the drug action two points deserve attention (1) where a drug acts and (2) How a drug acts?

Where a drug acts A drug may act locally, exactly on the tissues it comes in intimate contact with, either on the superficial epithelia of the skin, mouth, upper respiratory tract or other parts of the body where the drug can have direct access (also called direct or topical actions). A drug may act on certain particular tissues or organs having selective affinity by the absorption into the circulation. This is known as specific selective or systematic action of Basic concepts of Ayurvedic pharmacology 38

the drug.

Recent conceptions of drug action Whatever may be the mode of administration of a drug and its distribution in the body, it acts only when it reaches certain specific tissue cell either its surface or its interior. This is known as receptor theory. Highly potent drugs probably act on the tissue through certain receptors which are speculated to be localized on the surface of the cells or are parts of an enzyme system. These fitting like keys in the locks. Cell theory was described by Charak as “Sharira Avayavasthu Paramanu Bhedana Aprisanakyaya Bhavanti’. The action is achieved depending upon localization of receptors and the concentration of drug to which the receptor is exposed. If a drug acts by interaction with relatively non-specialized receptor, that is a receptor that serves functions common to most cells, its effects will be wide spread (Doshapratyanika action). If a drug interacts with specialized receptors its effects are more specific (Vyadhipratyanika action). Sometimes same drug may exercise different actions in the body by interaction with different Adhikaranas.

Enzymes The enzymes play an important part in the body activity and many drugs probably act through the enzymes.

These are known as pitta

modalities which take part in the drug metabolism.

How a drug acts Some of the drugs act purely by physical means. Oils applied externally to skin (Abhyanga) and internally (Ghritapan )act in this manner. Basic concepts of Ayurvedic pharmacology 39

Drug may act chemically by its chemical affinity it fixes up to certain tissues, or produces a new active substances at the nerve ends where it acts or it combines with some other substance in the blood or tissue and acts. Special action A drug may have well marked selective action on a particular part of the body even in minute doses. Most of the alkaloids act in this way. A drug may either increase (Vriddhi) or diminish the altered physiological functions of a particular type of tissue in disease and the result is either stimulation or depression of its function. Rasas have mostly local and some general effects till the digestion is completed. The Rasa, in the final form circulates through Rasa Dhatu all over the body and influences the doshas and metabolic processes. When it comes in contact with Doshas it increases or decreases them according to similar or dissimilar properties. Rasa, Guna and sometimes Virya have local action, while Vipaka and Virya have systematic action and Prabhava has got specific action. External administration (Bahiparimarjanam) of drugs are mostly directed towards local action while internal administration (Antah Parimarjam) towards systematic action.

ROLE OF VIRYA IN THE PHARMACOKINETICS OF DRUGS The term pharmacokinetics is used to describe the study of absorption. distribution, metabolism and excretion of drugs. Absorption and bio-availability of drugs play an important role in pharmacokinetics. Bioavailability of a drug is decided by the rate of appearance and the total amount of the active drug in the systemic circulation. The changes that a drug undergoes in the body and its ultimate excretion are considered as the fate of the drug. Alteration of a drug within a living organism is known as Basic concepts of Ayurvedic pharmacology 40

Bio-transformation. Charaka has envisaged the concept about the pharmacokinetics of drugs in the Kalpasthana as follows. The drugs that are Ushna (hot),

Tikshna

(acute),

Sukshma

(subtle),Vyavayi

(diffuse

and

antispasmodic) reaching the heart by virtue of their potency and circulating through the large and small blood vessels, pervade the entire body. They liquefy the accumulated morbid matter therein by virtue of their quality and break up their acuteness (ch. Kal.l).

In this verse the drug absorption,

systematic circulation of the drug throughout the body with certain qualities and specific actions on Malas was described. This gives generalized picture about the pharmaco-kinetics of drugs described in Ayurved. Charaka has put in his observation in Sutrasthana about the excretion of malas with the action of drugs or certain pre-operative process for Sodhana karma as – After a person has taken the oleation he should be under observation for muhurta (48minutes). One should recognize the liquefaction of morbid humor by the appearance of perspiration of the body, the dislodgement of morbid humors from their seats by horripilation; it’s reaching the stomach by the distension of the belly, its separation and upward course by belching and salivation (ch.sut.15). Virya is a fundamental principle of drug action which dominates all the other principles such as Rasa, Guna and Vipakas. The action of drug is determined mostly by Virya. In view of Charaka, any principle which is responsible for action is Virya has been grouped in to two as Sita and Ushna which represent the primordial factors of Soma and Agni – initiators of creation of living world. Virya has been classified into two and eight types. Eight Gunas out of twenty have deemed to be potent enough and they were conferred by the Virya status. They are Laghu, Guru, Sita, Ushna, Snigdh, Ruksha, Mrudu, and Tikshna. These eight viryas play an important role in Basic concepts of Ayurvedic pharmacology 41

the pharmacokinetics of every drug. Snigdha and Ruksha Viryas invariably influence the digestion of drugs in the gastrointestinal tract. The out come after these chemical reaction by snigdha and Ruksha Virya is absorbed and conveyed into the systematic circulation with the influence of Sita and Ushna Viryas and pervaded to all the cells. Drug acts either on the cell wall or intracellular substance and exercises it’s final action by Guru and Laghu Viryas. End product of entire reactions in excreted through Malas which are conveyed to certain excretory organs by Shita and Ushna Viryas. In fact all the 8 Viryas can be incorporated into two groups only. Shita Group – Snigdha, Guru, Mrudu. Ushna Group – Ruksha, Laghu, Tikshna. Any ingested drug is subjected to Jatharagnipaka, Bhutagnipaka and Dhatwagnipaka. The so called Paka Kriya is Agneya Pradhana. So Ushna Virya plays a main role in the drug metabolism, while Shita Virya also having equal, opposite and most important role in pharmacokinetics. One can admit without hesitation that Virya occupies an important place in explaining the pharmacokinetics of Ayurvedic drugs. But most scientific approach is imperative for the comprehension of the exact role of Virya.

Basic concepts of Ayurvedic pharmacology 42

GUNA The Gunas are of three types – (i) those constituting the distinctive features of the five elements, (ii) those common to five elements and (iii) those relating to the soul. The Gunas of the first category are sound (Sabda), touch (Sparsa), vision (Rupa), taste (Rasa) and smell (Gandha) constituting the distinctive features of Akasa, Vayu, Agni, Ap, and Prithvi respectively. Those of the second category are heaviness (Guru), lightness (Laghu), coldness (Sita), heat (Ushna), unctuousness (Snigdha), roughness (Ruksa), dullness (Manda), sharpness (Tikshna), immobility (Sthira), mobility (Sara), softness (Mridu), hardness (Kathina), non-slimness (Visada), sliminess (Picchila), smoothness (Slaksana) and liquidity (Drava). The Gunas of the third category are intellect (Budhi) including memory (Smriti), consciousness (Chetana), patience (Dhriti) and ego (Ahamkara) etc., desire (Iccha), hatred (Dvesa), happiness (Sukha), misery (Duhkha), efforts (Prayatna) predominance (Para), subordination (Apara), propriety (Yukti), number (Samkhya), combination (Samyoga), division (Vibhaga), separation (Prithakiva), measurement (Parimana), transformation (Samskara) and repetition (Abhyasa). The one which is a substratum of the qualities and actions and which is a concomitant cause is the matter. By definition, matter happens to be the substratum of qualities and Basic concepts of Ayurvedic pharmacology 43

actions and it is also the concomitant cause of another matter and qualities as well as actions. The capacity to produce something out of its own rests only in the matter. Neither the qualities nor action can produce something out of their own.

So the matter and not the qualities or action can constitute

concomitant cause. Guna possesses inseparable concomitance; it is the cause and devoid of efforts. Chakrapani interprets that “Unlike Karma, Guna is devoid of any (curative) efforts.

Besides, Guna has also inseparable concomitance as

distinct from Akasa, etc.

Which though devoid of efforts do not have

inseparable concomitance as their substrata.

Similarly, Karman is quite

distinct from gross matter which forms the substratum for action. Unlike generic concomitance (Samanya), variant factor (Visesa) and inseparable concomitance (Samanya), which do not constitute causes, Guna represents a causative factor as well. However, to say that the Guna is the cause is only partially correct.”

KARMA (ACTION) Karma (action) present in the matter is the cause of combination and separation. Karma is the action relating to something to be achieved. It does not require any other factor for its action. Action is simultaneously the cause of combination and separation. While combination does not cause separation and Vice Versa, the action present in the matter causes both combination as well as separation. Karman does not require any other subsequent help in the process of causing separation from the previous position as well as combination with Basic concepts of Ayurvedic pharmacology 44

the subsequent position. Although matter is simultaneously a factor for causing combination and separation, still it is so only when it possesses Karma. Karman, on the other hand, does cause combination and separation as soon as it is produced without requiring any other subsequent help except the proximity to the substratum of the combination and separation. By definition, Karma here implies only the action relating to something to be achieved (like the action of drugs, etc.) and not something like Vamanakarma (emetic therapy) or Adristakarma (invisible past action). Charaka categories dravyas into three groups i.e. Doshaprasamaka (alleviate doshas), Dhatu pradushana (vitiate dhatus) and Swasthahita (maintenance of positive health).

In this classification Doshas include

Dhatus and vice-versa. So the drugs that are designated as alleviators of the doshas also alleviate dhatus. Similarly the drugs that are designated as vitiators of the dhatus do as well vitiated doshas. The drugs under third category are those which have potentialities to prevent the diseases. These drugs are useful for maintenance of the equilibrium of the tissue elements so that they are neither aggravated nor decreased and help in the normal functioning of the body. Charaka has furnished the following pharmacological actions with certain examples.

1. Jeevaniya Varga (Invigorators) 2. Brimhaneeya Varga (Nourishing drugs) 3. Lekhaniya Varga (Reducing corpulency) 4. Bhedhaneeya Varga (Cathertics) Basic concepts of Ayurvedic pharmacology 45

5. Sandhaneeya Varga (Healers of wound) 6. Deepaniya Varga (Digestive stimulants) 7. Balya Varga (Strength Promoters) 8. Varnya (Complexion Promoters) 9. Kantya Varga (Useful for throat) 10. Hrudya Varga (Cardiac tonics) 11. Tripthighna Varga (Removes the sense of Pseudo contentment) 12. Arshoghna Varga (Anti-haemorroidals) 13. Kushtaghna Varga (Curatives of all skin diseases): 14. Kandooghna Varga (Anti pruritics) 15. Krimighna Varga (Anti- infectives) 16. Vishaghna Varga (Anti-toxics) 17. Sthanyajanana Varga (Galactogogues) 18. Sthanya shodhana Varga (Galacto-purificators) 19. Shukrajanana Varga (Spermatopoitics) 20. Shukra shodhana Varga (Spermato purificators) 21. Snehopaga Varga (Adjuvents of unction) 22. Swedhopaga Varga (Adjuvents of fomentation) 23. Vamanopaga Varga (Adjuvents of emesis) 24. Virechanopaga Varga (Adjuvents of purgation) 25. Asthapanopaga Varga (Adjuvents of decoction enema) 26. Anuvasanopaga Varga (Adjuvents of oil enema) 27. Sirovirechaneeya Varga (Adjuvents of for elimination of Doshas from the head) 28. Chardinigrahana Varga (Anti emetics) 29. Thrusna Nigrahana (Thirst restraining drugs) 30. Hikkanigrahana Varga (Anti- Hiccup) 31. Pureeshasangrahaneeya Varga (Anti – Diarrhoeal) Basic concepts of Ayurvedic pharmacology 46

32. Pureeshavirajaneeya Varga (Bowel Anti- discoloringagents) 33. Moothra Sangrahaneeya Varga (Anti diuretics) 34. Moothravivarjaneeya Varga (Urinary anti- discoloring agents): 35. Moothravirechaneeya Varga (Diuretics) 36. Kasahara Varga (Antitussives) 37. Swaasahara Varga (Broncho dilators) 38. Swayathuhara Varga (Anti inflammatory / curatives of oedema) 39. Jwarahara Varga (Anti pyretics) 40. Sramahara Varga (Fatigue relievers) 41. Dahaprashamana Varga (Curatives of Burning syndrome) 42. Sheethaprashamana Varga (Curatives of cold) 43. Udardaprashamana Varga (Curatives of urticaria) . 44. Shoolaprashamana Varga (Antispasmodics) 45. Angamardhaprasamana Varga (Bodyache relievers) 46. Sonithastapana Varga (Blood purifiers) 47. Vedanasthapa Varga (Analgesics) 48. Sangnasthapana Varga (Restoratives of conciousness) 49. Prajasthapana Varga (Anti-abortificiants or procreators) 50. Vayahasthapana Varga (Rejuvenators) Chakrapani has rendered the following interpretation for certain karmas (pharmacological actions) delineated by Charaka. 1. Jivaniya – Drugs conducive to longevity (Ayushyam) are known as Jivaniya. 2. Triptighna – Kapha, when vitiated gives rise to a sense of pseudocontentment which tells upon normal health. Drugs, which remove that sort of pseudo-contentment are known as Triptighnas. Basic concepts of Ayurvedic pharmacology 47

3. Snehopaga – The drugs that help the process of unction achieved by fats etc., are known as Snehopagas.

Such drugs are known as

Vamanopagas as they help madanaphala etc. for emesis viz., honey, yashtimadhu etc. 4. Purisha Virajakeeya – such drugs as eliminate the vitiated doshas from faeces are known as purisha virajaneeya. 5. Mutra Virechaniya – Drugs which increase diuresis are known as Mutra Virechaniyas. 6. Udardaprasamana – Udarda in this context is to be taken as Sitapitta (Urticaria) but not the disease described in Maharogadhyaya (Sut.20). Otherwise the prescription of Tinduka etc. for the relief of udarda cannot be justified because these drugs are not useful for vata. 7. Sonitasthapana – Drug which restores blood in its pure form after eliminating its eliminating its vitiating doshas. 8. Vadanasthapana – In the event of physical pain, the class of drugs which eliminates that pain and restores the body to its normal state is known as Vedanasthapana. 9. Samjnasthapana – It is the category of drugs that restores consciousness. 10. Prajasthapana – The drug which eliminate procreational defects and thus restores embryo are known as prajasthapana. 11. Vayasthapana – The drugs useful for restoration of youth are known as vayasthapana. Sarangadhara has enumerated the following pharmacological actions; 1. Deepana (Appetisers) 2. Pachana ( Digestives) 3. Sodhana (Expungents) Basic concepts of Ayurvedic pharmacology 48

4. Samana (Palliatives) 5. Anulomana (Aperients) 6. Sramsana (Laxatives) 7. Bhedana (Purgatives) 8. Rechana (Cathartics) 9. Vamana (Emetics) 10. Chedana (Sacrificants) 11. Lekhana (Anti-obese) 12. Grahi (Water absorbants and bowel binders) 13. Sthambhana (Constipative and bowel binder) 14. Rasayana (Rejuvenator) 15. Vajeekarana (Aphrodisiac) 16. Sukrala (Spermagogue) 17. Sukra pravartaka (Semen ejaculator) 18. Sukra Sthambhaka (Semen anti-ejaculator) 19. Sukra Soshaka (Semen dehydrant) 20. Sukshma (Subtle Penetrator) 21. Vyavayi ( 22. Vikasi ( 23. Madaqkari (Intoxicants) 24. Pramathi ( 25. Abhishyandi (Obstructants) Susruta has introduced certain pharmacological actions of the drugs indicated in various surgical procedures Viz; Romasnjanana (Hair growth promoters), Romasatana (Depilators), Savarnikarana (Inducer of pigmentation), Vranaropana (Wound healers) etc.

Basic concepts of Ayurvedic pharmacology 49

Ayurvedic pharmacological science identified certain novel pharmacological actions viz. Sukrasodhana (Semen purifiers) Sthanyasodhana (Breast milk purifiers) Sonitasthapana (Blood purifiers) Medhyarasayana (Brain tonics / Memory boosters) Vajeekarana (Aphrodisiacs) Rasayana (Rejuvenators) Chakshusya (Eye tonics) Kesya (Hair tonics) Dantya (Tooth and Gum tonics) The scientists of modern pharmacology may take another century to develop the drugs possessing the actions enumerated above. If the blood culture report shows the growth of infective organism and the semen analysis indicates the presence of pus cells one has to accept that blood and semen are not pure and requires drugs which can restore normalcy of these tissues / liquid substances. Modern medical scientists have initially not accepted the claims of Ayurvedic aphrodiacs. After the invention of Viagra they are constrained to accept the pharmacological actions described in the Ayurvedic medical science.

Basic concepts of Ayurvedic pharmacology 50

RASA (TASTE) Rasa or taste is the object of gustatory sense organ, and distinct from the objects of the other sense organs. Rasas in a substance and formed by different combinations of Mahabhutas. There are only six types of tastes viz., Madhura (sweet), Amla (sour), Lavana (saline), Katu (pungent), Tikta (bitter) and Kashaya (astringent).

The source material for the

manifestation of all these tastes is Jalamahabhuta. The qualities of preceding basic elements (Akasa, Vayu, Agni, Ap and Prithvi) are included in the succeeding ones; so the qualities of Ap is automatically included in Prithvi. Ap and Prithvi are the substrata for the manifestation of taste (Rasa). That is to say, taste (Rasa) can manifest itself only through Ap and Prithvi.

Rasa-Anurasa (Primary and secondary tastes) Among tastes present in a substance that which is clearly manifests (perceived, recognised) is designated as Rasa (chief/primary taste) and others which are not clearly manifest or which are understood (recognised) at the end are Anurasa (secondary tastes). Vagbhata further quotes about the gustatory effect of the initial as well as final contact of a dry as well as wet substance with the tongue are known as Rasa or taste. When such an effect is not distinctly perceptible but is inferred only by its actions, it is known as Anurasa (after taste).

Formation of six Rasas: The moon is the presiding diety of water.

The water in the

atmosphere (before it falls on the ground) is by nature cold and light, and its Rasa is not manifested at this stage. The moment it starts falling from Basic concepts of Ayurvedic pharmacology 51

atmosphere and after it falls on the ground, it gets impregnated with the qualities of the five Mahabhutas and it nourishes the individuals belonging to the vegetable and animals kingdom. At this stage the six tastes manifest themselves in these individuals. Of the six tastes, sweet taste abounds in the qualities of Jala Mahabhuta, sour taste of Prithvi and Agni, saline taste of Jala and Agni, pungent taste of Agni and Vayu, bitter taste of Vayu and Akasa and astringent taste of Vayu and Prithvi. So like the individuals belonging to the vegetable and animal kingdom of diverse types, depending upon their colour and shape (owing to the predominance or otherwise of the various Mahabhutas), the Rasas are also six in number due to the predominance or otherwise of the five Mahabhutas in turn depends on the six seasonal variations. As a mater of fact, all the five Mahabhutas are there in al the six Rasas but the manifestation of the various Rasas depends on the predominance or otherwise of the qualities of one or more of the Mahabhuta, for example, Jala Mahabhuta is the root cause of all the six Rasas but it predominates in sweet taste and as such it constitutes a distinctive causative factor thereof.

According to Susruta, saline taste is dominated by the

qualities of Prithvi and Agni. This apparently goes against the observation made above. But as a matter of fact there is no contradiction so far as the manifestation of saline taste is concerned. One might ask: if the saline taste is caused by the predominance of Agni and Jala which are hot and cold respectively the resultant substance having saline taste should also have both hot and cold qualities; but how is it that salt is said to be of hot quality? The reply is, it is not that the involved in the composition of substance always Basic concepts of Ayurvedic pharmacology 52

manifest all of their qualities for example, Jala Mahabhutas brings about sweetness and not unctuousness in Makusthaka (Phaseolus aconitifillus Jacq.); similarly even though Agni Mahabhutas predominates in the composition of rock salt, the latter does not possess heating property. The combination of the Mahabhutas in a particular way and the diversity of their manifestation are guided by some imperceptible factors which can only be inferred from the manifested effect of the substance. For example, salt posses heating and sticking properties and so it inferred that Agni and Jala Mahabhutas dominate in its composition. If fact we mortals cannot easily comprehend such combinations and their effects.

They can only be

ascertained from scriptures. To cite another example, we cannot offer any rational explanation as to how the Mahabhutas in isolation (other than Jala) do not cause any other Rasa. This proves that there is something inherent in the five Mahabhutas themselves which is responsible for their combinations and manifestation of their effects in various ways. The five Mahabutas constitute the efficient cause for the manifestations of the specific types of Rasa like sweetness etc.

it is therefore immaterial whether all the

Mahabhutas in themselves posses Rasas or not. Agni for example does not posses any Rasa but it is still an efficient cause for the manifestation of a Rasa like sourness.

Inter Relationship of Ritu & Panchamahabhuta: The seasonal variations result in the predominance or otherwise of the qualities of the five Mahabhutas and bring about the manifestation of the various Rasas thereby. For example, in Hemanta (November-January) the qualities of Jala Mahabuta manifest themselves in excess, resulting in the production of drugs and deits having sweet taste; in Sisira (January-March) Vayu and Akasa predominate, resulting in the manifestation of bitter tastes. Basic concepts of Ayurvedic pharmacology 53

Even day and night and some other imperceptible factors are responsible for the predominance of the one or the other of the Mahabhutas. Thus it is not that in the Hemanta (November-January) every drug and diet will always have sweet taste. There is a possibility of manifestation of other Rasas as well, depending on the effect of other imperceptible factors. As a matter of fact the predominance of Mahabhutas is responsible for the seasonal variations and vice-versa. This inter-dependence may be compared to the inter-dependence of the seed and the embryo.

Guru (heaviness) and other Gunas (qualities) present in the Prithvivyadi Dravyas (substances of Prithvi and other Bhuta predominance) are residing in the Rasas (tastes of those substances); they (Gunas) are ascribed to (attributed to) the tastes, because of intimate co-existence. Actions of different Rasas: Madhura Rasa: Drugs possessing Madhura Rasa  Wholesome to the body  Add to the growth of seven body tissues  Imparts long life  Soothing to the six sense organs  Promote strength and complexion  Alleviate Pitta, Vata and effects of poison  Relieve thirst and burning sensation  Promote healthy skin, hair, voice and strength  Soothing, invigorating and nourishing  Bring about stability and heal up emaciation and consumption  Soothing to the nose, mouth, throat, lips, tongue and relieve fits.  Much liked by bees and ants.  They are cold, unctuous and heavy. Amla Rasa:

Basic concepts of Ayurvedic pharmacology 54

Drugs possessing Amla Rasa            

Add to the deliciousness of food Stimulate appetite Nourish and energize the body Enlighten the mind Strengthen the sense organs Promote strength Alleviate Vata Nourish the heart Cause salivation Help in swallowing, moistening and digestion of food Refreshing They are light, hot and unctuous. Lavana Rasa:

Drugs possessing Lavana Rasa            

Help in carmination, production of stickiness, digestion, osnosia, excision and incision Sharp, mobile, Vikasi and laxative. Avakasakara (deobstructent) Alleviate Vata Cure stiffness, obstruction and accumulation Nullify the effect of all other tastes Cause salivation Liquefy Kapha Clarify the channels of circulation Bring about the tenderness of all the bodily organs Cause deliciousness and essential ingredients of food They are neither heavy & unctuous nor hot. Katu Rasa:

Drugs possessing Katu Rasa     

Keep the mouth clean Promote digestion Help in absorption of food Cause secretion through nose, lacrimation Help proper action of sense organs Basic concepts of Ayurvedic pharmacology 55

     

Cure diseases like Alasaka, Swayadhu, Udarda, Abhishyandi, Kandu, Vrana, Krimi Allay excessive growth of ulcers Corrode the muscle tissue Break blood clot and other obstructions Clear the passages They are light, hot and ununctuous. Tikta Rasa:

Drugs possessing Tikta Rasa        

Promote deliciousness Antitoxic and germicidal Cure fainting, burning sensation, itching, skin diseases including leprosy, thirst and fever Promote firmness of skin and muscles Promote carmination and digestion Purify milk Cause dry and help in depletion of moisture, fat, muscle fat, bone marrow, lymph, pus, sweat, urine, stool, Pitta and Kapha They are ununctuous, cold and light.

Kashaya Rasa: Drugs possessing Kashaya Rasa      

Palliative, constipative and promotive Produce pressure on the affected part Cause healing, absorption and stiffness Alleviate Kapha, Rakta and Pitta Absorb the body fluid They are ununctuous, cold and heavy.

Drugs having sweet, sour and saline taste alleviate Vata; those having astringent, sweet and bitter (tastes) alleviate Pitta and those having astringent, pungent and bitter (tastes) alleviate Kapha.

Basic concepts of Ayurvedic pharmacology 56

The relative superiority or inferiority of the tastes of drugs of various categories is as below. Property Superior Moderate Inferior Unctuousness Sweet Pungent Bitter Dryness Astringent Sour Saline Heating Saline Sour Pungent Cooling Sweet Astringent Bitter Heaviness Sweet Astringent Saline Lightness Bitter Pungent Sour Determination of Virya – Vipaka according to Rasa: The drugs and diets which are sweet in Rasa (taste) and Vipaka (taste after digestion) are of Sitavirya (that is potentially cold); those with sour or pungent taste and Vipaka are of Ushnavirya (that is potentially hot). Only such of the drugs and diets which are sweet in taste as well as Vipaka are of Sitavirya.

One cannot determine Sitavirya (or potential

coldness) of drugs and diets only on the basis of sweet taste. The same principals is applicable to the drugs and diets of Ushna type as well. The properties of such of the drugs and diets as possess Virya and Vipaka in conformity with Rasa are explained here only in terms of Rasas concerned. Thus the physician may explain the properties of milk, ghee, Cavya (Piper Chaba Hunter) and Chitraka (Plumbazo Zeylanic Linn.) on the basis of their tastes. Drugs and diets having sweet taste and sweet Vipaka are generally of Sitavirya (potentially cold). Similarly those of sour and pungent taste and pungent Vipaka are Ushna Virya (potentially hot). In the case of such of the drugs and diets where Virya and Vipaka are in conformity with Rasa, their properties are explained in terms of Rasa only.

As for example the

Basic concepts of Ayurvedic pharmacology 57

properties of milk and ghee both of which are sweet in taste and Vipaka and Sitavirya can be ascertained in terms of their taste only. The above principle does not apply in the cases of such of the drugs and diets where Virya (potency) is not in conformity with Rasa. Some drugs having sweet taste are of Ushnavirya (potentially hot) e. g. the meat of aquatic and marshy animals. Some drugs having astringent and bitter tastes are also of Ushnavirya (potentially hot) e.g. drugs belonging to Mahat Panchamula group (Aegle mamelous Corr.), Oroxylum indicum Vent.,

Gmelina

arboria

Linn,

(Stereospermum

suaveloens

Dc.,

Clerodendrum phlomidis Linn. f.), Arka (Calotropis gigantean R.Br.), Aguru (Aguilaria agalocha Roxb.) and Guduchi (Tinospora cordiofolia Miers) – all the latter three having bitter taste. Similarly rock salt having sour taste is not of Ushna Virya (potentially hot). Some drugs having sour taste are costive, e.g. Kapittha (Feronia limonia Swingle); some are laxative, Gaertn).

e.g. Amalaka (Emblica officinalis

Even though drugs having pungent taste are generally non-

aphrodisiac, still Pippali (Piper longum Linn.) and Sunthi (Zingiber officinale Rosc) having pungent taste are generally non-aphrodisiac, still Pippali (paper Longum Linn.) and Sunthi (Zingiber Offcinale Rosc.) having such taste are aphrodisiac.

Similarly drugs having astringent taste are

generally of Sitavirya and costive but Haritaki (Terminalia chebula Linn.) is an exception to – it is Ushnavirya and laxative. Thus it is not possible to explain the properties of all the drugs and diets simply in terms of Rasa because individual drugs having identical tastes vary in relation to their properties. **** Basic concepts of Ayurvedic pharmacology 58

VIPAKA

The ingested food or drug gets digested by the Jatharagni (digestive enzymes). The properties that emerge thereafter are known as Vipaka. It is not the taste, but the drugs having different tastes which undergo transformation in the form of Vipaka. Vipaka of drugs and diets having pungent, bitter and astringent tastes is pungent that of sour taste is sour and that of sweet and saline tastes is sweet. Pungent Vipaka aggravates Vata, reduces semen and obstructs the passage of stool and urine.

Sweet Vipaka aggravates Kapha, promotes

semen and helps in the proper elimination of stool and urine. Similarly sour Vipaka aggravates Pitta, reduces semen and helps in the proper elimination of stool and urine. Sweet Vipaka is heavy; pungent and sour are light. The relative superiority or inferiority of various types of Vipaka can be determined on the basis of the relative superiority and inferiority of the various properties of different drugs and diets.

Views of different commentators about the types of Vipaka: Some commentators are of the view that every Rasa has its own Vipaka. Accordingly, there are six Vipakas corresponding to the Rasas. Some others say that if there are more than one Rasa, only the strongest of them predominates. So the Vipaka cannot be correctly predicted. Susruta on other hand does not agree with any of the two views enunciated above about the unpredictability of Vipaka. In his opinion there are two Vipakas viz, Basic concepts of Ayurvedic pharmacology 59

sweet and pungent in such of the drugs and diets where Prithvi and Jala Mahabhutas are dominant, the Vipaka is sweet; where the lighter Mahabhutas like Tejas, Vayu and Akasa are dominant, the Vipaka is pungent-cf. Susruta: Surta 40: 11-12. It is true that according to the theory which admits of one corresponding Vipaka for each of the Rasas and also according to the theory which establishes the fact that only the strongest Rasa predominates in the Vipaka stage, the drugs and diets do not undergo any change in the Vipaka stage. That is to say the properties of their Rasas continue to be the same even in Vipaka stage. Thus the stand taken by Susruta in disregarding these two views is quite justified. The only flaw in Susruta’s view point is that he does not accept the third Vipaka which is sour. If this sour Vipaka is not accepted, Vrihi (a type of paddy) and Kulattha (Dolichos biflorus Linn.) which are of sweet and astringent taste respectively but whose Vipaka is sour will remain unexplained and the statement regarding their action viz. the aggravation of Pitta would not hold good. It is not correct to say that will remain unexplained and the statement regarding but whose Vipaka is sour will remain unexplained and the statement regarding their action viz. the aggravation of Pitta would not hold good. It is not correct to say that Vrihi etc., cause the aggravation of Pitta due to their hot potency. Even if it is accepted that Vrihi is of hot potency, this potentiality would rather get superceded by the sweetness in its taste as well as its Vipaka. Moreover, the Pitta aggravated by Vrihi etc., abounds in sour taste. Had it been due to the hot potency of Vrihi, it would have rather abounded in pungent taste which is not corroborated by actual experience. For the eructation after the intake of Vrihi etc. is always of sour taste. Besides according to Susruta, sweet Vipaka is caused by the predominance of Prithvi and or Jala Mahabhutas and pungent Vipaka by the predominance of the rest. Now the question arises what would be the Vipaka if there is Basic concepts of Ayurvedic pharmacology 60

overlapping in the combination of the Mahabhutas? The resultant Vipaka cannot be either sweet or pungent but a third one which as mentioned above, can only be the sour Vipaka. Or better we may leave out the discount as to whether there is a sour Vipaka or not. What Charaka characterizes as sour Vipaka, Susruta as of hot potency.

There is in fact no contradiction

whatsoever about the properties of the various drugs and diets in either of the theories. Susruta would have, however, done well not to point our any flaw (vide Susruta: Susruta 40:10) in the sour Vipaka theory enunciated by Charaka. Saline taste results in sweet Vipaka, and bitter and astringent tastes in pungent Vipaka. But how is it that drugs and diets having saline taste cause aggravation of Pitta and Rakta, and those with bitter and astringent taste alleviate Pitta? Even if the saline taste results in sweet Vipaka, its not potency is responsible for the aggravation of Pitta and Rakta. Normally, sweet Vipaka is responsible for the aggravation both Pitta and Rakta but being over powered by the hot potency it is ineffective. Sweet Vipaka of such drugs and diets however manifests ineffective. Sweet Vipaka of such drugs and diets however manifests itself in the form of the proper elimination of stool and urine etc. Thus sweet Vipaka may not be effective in so far as the aggravation of Pitta and Vata is concerned but it is effective with regard to the therapeutic aspects. Similarly, the pungent Vipaka of drugs and diets having bitter and astringent tastes cannot be explained. Some commentators have tried to explain it in a slightly different manner. They connect the clause ‘Lavanastatha’ with ‘Amlam’ and so they interpret it to mean that Vipaka of saline taste is also sour rather than sweet and as such they find it more convenient to explain the correlation between Basic concepts of Ayurvedic pharmacology 61

saline taste and aggravation of Pitta and Rakta. But Jatukarna is very clear in his statement about three-fold classification of Vipakas as follows: The Vipaka of pungent, astringent and bitter tastes is pungent, that of sour taste as sour and that of sweet and saline tastes, as sweet. Why cannot we accept six Vipakas corresponding to the six tastes? We cannot. Because the three-fold classification of Vipakas depends on the real process of transformation of the five Mahabhutas which cannot be questioned. As stated above, there is apparently no difference between the Rasa and Vipaka of drugs and diets having sweet, sour and pungent tastes. It may now be argued that such of the Vipakas where there is some variation from the original taste (viz. sweet Vipaka for saline taste or pungent Vipaka for bitter and astringent tastes) could well be explained in order to avoid confusion. But what was the necessity of explaining the Vipakas of identical taste? It was necessary to recognize the two distinct levels as the original Rasa and Vipaka (that is the taste after the substance is digested). That is why the original pungent taste of Pippali (Piper longum Linn.) is therapeutically useful for the elimination of phlegm from the throat and purification of mouth. But its sweet Vipaka renders it aphrodisiac action in its final effect. One thing is however clear. Where the original taste and Vipaka are identical, the properties of drugs and diets are more effective. They are not so in the cases where there is variation between the original taste and Vipaka. The three-fold classification of Vipaka as described above is different Basic concepts of Ayurvedic pharmacology 62

from the three Avasthapakas described in the fifteenth chapter of Charaka Chikitsasthana.

While the latter confines itself to the various stages of

digestion, the former is specific to individual drugs and diets. All drugs and diets having various tastes undergo the three Avasthapakas but Vipaka varies from individual to individual.

Actions of Vipaka Susruta quotes - Guru Vipaka alleviates Vata and Pitta while Laghu Vipaka is Kapha-alleviating; amongst them, soft, cold and hot are perceived by touch; slimy and non-slimy by vision and touch; unctuous and nonunctuous by vision and sharp by producing pain in mouth. Guru Vipaka by eliminating faeces and urine and aggravation of Kapha while Laghu Vipaka by retaining faeces and urine and aggravation of Vata. According to Charaka    

Katu (Pungent) Vipaka aggravates Vata, reduces semen and obstructs the passage of stool and urine. Madhura (Sweet) Vipaka aggravates Kapha, promotes semen and helps in proper elimination of stool and urine. Similarly Amla (Sour) Vipaka aggravates Pitta, reduces semen and helps in proper elimination of stool and urine. Madhura Vipaka is heavy; Katu and Amla Vipaka are light.

Panchamahabhutas in the formation of Vipaka: Madhura Paka emerges when qualities of Ap and Prithvi appear predominantly while Dravyas are being digested; (on the contrary) when qualities of Tejas, Vayu and Akasa are predominant during digestion of Dravyas, Katu Paka emerges.

Basic concepts of Ayurvedic pharmacology 63

VIRYA

Etymon of word Virya: According to the various Sanskrit dictionaries and Koshas, it is apparent that the word Virya is derived from the Root Veer or Vri meaning “Vikranti” or specific power to express Vigour etc.

Different meanings of Virya in various literatures: According to Vedic literature and the commentary of Sayana there on “Virya” means, the special capacity (Samardhya) not only necessary for physical and mental activity but also that which is necessary for worldly capacity to possess different kinds of wealth, like Pasu, Putra, Dhana etc. The word Virya is used simply for physical capacity of a human being and references are available from Manusmruti, Vedas and Bhagavata Puranam. Amarkosha has mentioned the meaning of Virya as “Utsaha”. The ordinary Utsaha is not known as Virya but such an overwhelming exertion requires extraordinary vitality and for such purpose the required amount of vitality is produced by Virya. In the ancient Sanskrit literature the meaning of word Virya is ascribed to Sukra Dhatu as well as for male genital organ. In the Ayurvedic literature the Virya is used for Shakti or energy through which drug acts in the body.

Source Material of Virya: Different concepts of Virya are described in different texts. Mainly 3 concepts are mentioned namely (i) Shakti Viryavada (ii) Guna Viryavada or Paribhashika Virya Vada consisting of Dwividha and Ashta Vidha Viryas (iii) Karma Viryavada. Basic concepts of Ayurvedic pharmacology 64

Charakian system has delineated Virya as Shakti and defined it I its own verses as “Ena Kurvanti Tat Viryam”. Chakrapani Datta has implied the term in general for Rasa, Guna, Vipaka and Prabhava. So this Vata named as Shakti Virya Vada or general concept of Virya. Charak has also mentioned contemporary view of Ashta Vidha Viryas while describing Diwvidha Viryas-ushna & sheeta. Gangadhar in his “Jalpakalpataru” has taken Virya as the instrument or tool (Upakaranas)of the drug to perform its action. Yogendranath Sen a commentator on Charaik Samhita issued a statement that “Vryantu Kriyantu Yena Ya Kriya” was the Charaka’s original as well as accepted concept where as Ashtavidha Virya Veda were not accepted by him.

But frankly speaking this is incorrect as no other contradictory

statement was written about the number of Viryas. Shusruta has denoted the Virya as the generator of any drug action. Acharya Sushruta put forth the Ashtavidha Viryavada taking eight Gunas out of twenty Gunas which are having Utkrishtata. But Visada, Pichchila were mentioned in the place of Guru and Laghu. The eight Gunas are – Snigdha, Ruksha, Sheeta, Ushna, Mrudu, Tikshna, Visada and Pichchila. He has also stated the Dwividha Virya Vada known as Ushna-Sheeta.

Dalhana

commenting on Sushruta’s Verse stated Achintya and Chintya Viryas. The former was denoted as Prabhava. Vagbhata followed the Charka’s school of thought and also Sushruta’s observations. But regarding Ashtavidha Viryas Guru-Laghu were mentioned instead of Visada-Pichchila. Hemadri has made a reference to the view that “Viryas are many” and observed that “though Virya has been described of two types, it can still be as many as there are actions to be performed. In this view, all actions Basic concepts of Ayurvedic pharmacology 65

regardless of Gunas, are due to Virya and therefore, there can be as many Viryas as there are actions. The other significant clarification offered by Hemadri which have direct bearing on the subject now under study is “that which evokes taste perception is Rasa and all rest are Gunas. Particular or distinct –Vishishta Rasa –or taste that occur as the result of Kayagnipaka is Vipaka and produced Guna at this stage is Virya. Arunadatta has stated that Gunas are only Viryas but not Rasa as the latter cannot withstand the influence of Kayagnipaka and undergo changes. Indu in his “Seshilekha “commentary also supported the concept of multiplicity of Virya. Among Laghutrayee Bhavamishra has mentioned Virya in terms of Shakti. Sarangadhara has written life span of Virya of different pharmaceutical preparations,

eg. Churna will be possessing Virya Up to 2

months. Badanta Narguna envisaged the Karma Viryavada by furnishing a definition for Virya as “Karmalakshanam Viryam”. Guna Viryavada was subjected to severe criticism by Acharya Nagarjuna.

He has described

Chardaniya Virya, Anulomana Virya etc. Nimi has mentioned 15 types of Viryas such as Urdhwabhagahara Virya, Adhobhagahara Virya etc. Shivadas Sen has observed that Virya is a special power.

The

uniqueness of Virya has been stressed by him as he observes – Shakti is Virya. It alone is capable of performing powerful actions. These actions do not suffer from any limitations due to non–attachment of viryas to Rasas. Virya is intimately correlated to Gunas viz., Ushna, Sheeta erc. Since Virya inheres inseparably in Dravyas, it is considered to be complementary to Rasas. Shivadas Sen propounded a different type of definition of Viryas as Basic concepts of Ayurvedic pharmacology 66

follows-It is not the quality of the substance, but it is the fraction of substances itself, capable of performing a special action, and also derived from the very important part of the Panchabhutic structure of the Dravya itself. He has also mentioned Sahaja and Kritrima Viryas. Some of the scholar of twentieth century have interpreted Virya as active principles of the drug. Prof C. Dwarka Nath has interpreted Sheeta and Ushna Virya as potential and kinetic energies. To sum up and summarize, the fundamental principles of drug action Virya has been with in different aspects such as Shakti, Utkrishta Gunas and Karmas. Virya was numerically expressed as Dwividha, Ashtavidha and Bahuvidha. Recent scholars and scientists of present era have interpreted it as active principle and energy modalities such as potential and kinetic energies.

Dwividha Virya vis-à-vis Ashtavidha Viryas: The term Virya has been described as Shakti or power to perform work of any kind. Both Charka and Susruta have described it as that which performs work and interpreted it into two or eight Gunas. Vagbhata has noted that, in the opinion of some, Viryas are two. They are Ushna and Sheeta. He has added that even though the things of universe as appeared to be diverse and represent a heterogeneity, they can be classified as of two kinds viz., Avyakta (Nominal) and Vyakta (phenomenal), and they never supercede the two most powerful aspects of nature viz., Agni and Shoma. On the other hand Ashtavidha Viryavada was postulated taking eight potent Gunas out of 20 viz., Mrudu-Tikshna, Snigdha –Ruksha, Guru-Laghu and Sheeta Ushna. Vagbhata has referred to authorities of eminence of Charaka, Basic concepts of Ayurvedic pharmacology 67

according to whom these 8 Gunas are relatively more important, in view of their being the essence of the twenty, their potency in action and their importance in the descriptions of the actions of Dravyas as compared to those of the Rasas.

The twelve Gunas out of twenty disappear in

Kayagnipaka and leave behind 8 Gunas. The eight Gunas on the other hand, are constant and they are generally not mutable. The Ashtavidha Virya Vada incorporates Dwividha Viryas and later included the former. The actions of different Viryas are given in the table 1.

S.No. 1.

Viryas Sheeta

Actions

Action On Doshas

Prahladana, Visyandana,

Pittasamana

Prasadana, Jivana,

Kaphavatakara.

Sthambhana. 2.

Ushna

Dahana, Pachana, Murchana, Swedana,

Kaphavatasamana

Bramatrishna Janana.

Pittakara.

3.

Snigdha

Snehana, Brimhana, Sanatarpana

Vatahata.

4.

Ruksha

Samgrahana, Pidana, Uparohana

Vatakara, Kaphahara.

5.

Guru

Upalepa, Brimhana, Vajikarana.

Vatahara.

6.

Laghu

Lekhana, Kledachushana

Kaphahara.

7.

Mrudu

Raktamamsaprasadana

Pittahara

8.

Tikshana

Sangrahi, Avadarana

Kaphara.

It is explicitly stated that drugs act not only by virtue of their qualities but in fact they act by virtue of their own nature or qualities or by both. Drug action was described in terms of Rasapanchak. Certain drugs manifest their action by virtue of their Rasa (taste). Some by virtue of their Virya (potency) or other qualities, some by Vipaka and others by their Prabhava Basic concepts of Ayurvedic pharmacology 68

(causative factor of specific action). In the modern pharmacology the drug action was described in terms of stimulation, depression and irritation of cellular functions which may be interpreted as Vriddhi and Kshaya of physiological activities in Ayurvedic parlance.

The Virgin “Tat Tat

Adhikaranam Ashadya” also reflects the recent receptor theory of drug action of modern pharmacology. A proper scientific footing to the general principles of drug action of Ayurveda may be conveyed by a comprehensive approach. The comprehensive term Virya is employed to explain lesser or greater potential factors in the drug in relation to different processes and procedures to achieve a desired effect in the body. Prof. C. Dwarakanath has summarized his views about Virya as follows – It is necessary, at this stage, to refer to the interrelationship that is started to exist between Rasas, Gunas and Viryas, as the suggested relationship between the three has an immediate bearing on the present study.

It may be recalled that Ayurveda has described ten Gunas or

qualities/properties viz., Guru, Manda, Hima, Snigdha, Shlakshna, Sandra, Mridu, Sthira, Sukshma and Vishada and their opposites viz., Laghu, Tikshna, Ushna, Ruksha, Khara, Drava, Kathina, Sara, Sthula and Pichchila – in twenty.

Important, as these Gunas are, Vagbhata has referred to

authorities of the eminence of Charaka, according to whom Mridu, Tikshna, Guru, Laghu, Snigdha, Ruksha, Ushna and Shita are relatively more important, in view of their being the essence of the twenty, their potency in action and their importance in the description of the actions of Dravyas as compared those of the Rasas. In regard to the latter, he has noted that the natural tastes of substances can be easily transformed or modified by combining them variously. The eight Gunas, on the other hand, are constant and they are generally not mutable. It is for this reason that they receive Basic concepts of Ayurvedic pharmacology 69

priority of consideration in all descriptions of substances. Since they are powerful in the performance of actions they are also described as Viryas. In this view, the eight, corresponding to the eight Gunas referred to above.

VIRYA OR ENERGY MODALITY: The term Virya, referred to in the foregoing, has been described as Shakti or power to perform work of any kind. Both Charaka and Sushruta have described it as that which performs work Ena kurvantitat viryam. Chakrapani Datta has also described it as Shakti Viryamiti shakti. Though in Sushruta’s view Virya is of two kinds viz., Ushna and Shita, he has however taken note of a contemporary view that Shita, Ushna, Snigdha, Ruksha, Vishada, Pichchila, Mridu and Tikshna represent the eight kinds of Virya. Dalhana has observed that Virya is Shakti, whether it is of two or eight kinds. The view referred to above notwithstanding, Sushruta has held that Ushna and Shita (Gunas)/Viryas transcend and supercede the specific actions ascribed to Rasas and that they act by virtue of their own inherent powers. He has observed that like the Agni and Shoma of the universe, Viryas are also two viz., Ushna and Shita. Vagbhata has noted that in the opinion of some, Viryas are two. They are Ushna and Shita. He has added that, even though things of the universe appear to be diverse and represent a heterogenity, they can be classified as of two kinds viz., Avyakta (nominal) and Vyakta (phenomenal), they never supercede the two most powerful aspects of nature viz., Agni and Shoma. The terms Agni and Shoma are Upanishadic in origin and usage. The former is spoken of as Pranam and the latter, Anna. Anaa or Shoma refers to the things of the universe that are susceptible to decomposition, disintegration or of being cooked Prana or Agni is the force/factor that is held to cause decomposition, disintegration or cooking of Anna or Shoma. Basic concepts of Ayurvedic pharmacology 70

In the Aupanishadic view, Anna or Shoma and Agni or Prana are in a state of mithuna or embrace and are inseparable, The inseparability of the two has been described as Rayi. In this view, all things orf the universe represent the two inseparable and fundamental modes of nature, namely, Agni, or Prana and Shoma or Anna, corresponding to Energy and Matter respectively. In the light of this concept, Ushna and Shita Viryas are, at the microcosmic levels-specially, at the bio-physical and bio-chemical levels-comparable to the two modes of Energy viz., the Kinetic and the potential. A concept, similar to the one referred to above, marks a more recent development in the field of modern theoretical physics. This has been succinctly described by I. Harris in his thought provoking book entitled “MAN’S PLACE IN THE UNIVERSE” as bellow:Energy is a force which makes the universe a working concern. Although it forms the basis of the most materialistic of all sciences – physics – it – is nevertheless, an invisible thing, imponderable, without shape or form. Energy becomes recognizable, as such only by its manifestation. All action and reaction of the living universe is merely an assertion of this all pervading power. Heat, light, chemical, gravitation, energy, all are cosmic forces which shape existence. All forms of energy are interchangable and can be transformed into another. Perhaps, the most significant fact in regarded to energy is that, in accordance with Einstein formula, E = MC2, matter can be transformed into energy. The electron, positron, in fact the whole material world is dissolvable into something which in terms of shape and form, are nothing. The visible and perceptible are mortal, finite, transitory, perishable. It is the realms beyond material existence in which we find the only thing which is permanent, eternal–energy. Basic concepts of Ayurvedic pharmacology 71

“Energy is found in two conditions in a latent, dormant, potential state or in a kinetic, that is active state. The potential and kinetic energy are of equal value. One state of energy incessantly passes over into another; incessantly it engenders metamorphosis in different forms-light, heat, lifeenergy. The whole living universe is simply a manifestation of this energy. Now it is dormant, now it is kinetic. It follows from one object to another but it never weakens, never spends its force. The sum-total of energy is the same now as it ever has been and remain the same for all time”. Proceeding on the basis of the earlier Ayurvedic concepts of Energy and Matter and, a similar concept developed by modern (theoretical) physics (extracted above), the twenty Gunas-comparing ten each of the oppositesrepresent the two fundamental modes of Energy.

These groups can be

broadly classified under two general categories viz., Anna and Parana or Shoma and Agni or Anudbhuta Shakti and Udbuta Shakti or Shita Virya and Ushna Virya and, in the parlance of modern physical-including chemical sciences, - the kinetic and potential energies, as shown in the table below.

Basic concepts of Ayurvedic pharmacology 72

TABLE 1 TWO BROAD BASED CLASSIFICATION OF TWENTY GUNAS S.No.

Anna or Shoma or Anudbhuta

Prana or Agni or Udbhuta-

Shita Virya or Potential

Shakti or Ushna Virya or

Energy

Kinetic Energy

1.

Guru

Laghu

2.

Shita

Ushna

3.

Snigdha

Ruksha

4.

Manda

Tikshna

5.

Sthira

Sara

6.

Kathina

Mridu

7.

Pichchila

Vishada

8.

Shlakshna

Khara

9.

Sthula

Sukshma

10.

Sandra

Drava

Though the twenty Gunas comprising ten each of the opposites represent, generally, two kinds of energy-modalities, all expect the eight, comprising four each of the opposites, shown in the table below, have been given the status of Viryas.

Basic concepts of Ayurvedic pharmacology 73

TABLE II EIGHT GUNAS WITH VIRYA STATUS S.No.

Annam or Shoma or

Prana or Agni or Udbhuta

Anudbhut Shakti or Shita

Shakti or Ushna Virya or

Virya or Potential energy

Kinetic energy

1.

Guru

Laghu

2

Snigdha

Ruksha

3.

Shita

Ushna

4.

Mridu

Tikshna

The status of Virya has been conferred upon the eight Gunas, in view, according to Vagbhata “of their being the Sara (essence) of the twenty Gunas; their effectiveness in the performance of actions and the importance attached to them in the description of the qualities of Dravyas (as compared to Rasas)”. In the remaining twelve Gunas, comprising six each of the opposites viz., Sthira, Sara, Kathina, Manda, Pichchila, Vishada, Sthula, Sukshma, Shlakshna, Khara and Drava, which have no Virya status-can, in this view be reduced to eight Gunas with Virya status. In this view, the eight Gunas, described as Viryas, are ultimately or finally resolved or reducible, in the course of Kayagnipaka to two Gunas or Viryas viz., Ushna and Shita. The manner in which the resolution or reduction is brought about has been aphoristically stated by Vagbhata thus: “Viryas are two because of the Utkarsha of the Ushna and Shita Gunas” the term ‘Utkarsha’ means, among others, ‘pulling of or upwards, elevation, eminence, increase, excess etc. Vagbhata’s aphorism, therefore refers to the act of being ‘Pulled up’ or the manifestation’ in excess’ of the Ushna and Shita Gunas, superceding or suppressing the remaining six-Gunas. In other words, these two Gunas represent the final outcome of the metabolism of Basic concepts of Ayurvedic pharmacology 74

nutrients and drugs. They alone are capable of performing actions in the body. Hemadri’s explanatory note on the foregoing in particular and, Gunas, Vipakas and Viryas in general, are extremely significant and valuable. Observes Hemadri: “Although the eight Gunas occur, in the course of Kayagnipaka, still the resultant Virya is of two kinds, according as the Ushna or Shita Guna is thrown up i.e., emerges surpassing the other GunasUtkarsha.

The tiraskara or disappearance of Gunas results in the

preponderance of Shakti. Because of this the term Virya is well-known all over the world as Shakti.” Hemadri’s explanatory note above draws attention to the final fate of nutrient substances to Kayagnipaka or metabolic transformations. In this view, the twenty Gunas, corresponding to various items of dietery-sweet, sour, saline, bitter, acrid and astringent-are reduced/resolved in to eight Gunas i.e., substances that exhibit these Gunas, in a first major step, in the course of their metabolism. In the second and, perhaps, the final metabolic step, the Gunas corresponding to metabolites which they reflect are reduced/resolved into two Gunas viz., Ushna and Shita.

These Gunas

represent the two fundamental modes of Energy which are effective in the performance actions. It will be seen from the above that substances to which the eight Gunas refer represent an intermediate stage between the twenty Gunas on the one hand and the two described as Viryas, on the other. To restate the eight intermediate Gunas pertain, obviously, to intermediate metabolites-the Malakhya and Prasadakhya Dhatus-in transit. Basic concepts of Ayurvedic pharmacology 75

The justification for the description of the several Gunas and, in particular, the fact that all material substances –Sarvbhava-are endowed with limited power-Parishvakta or Pratiniyata Shakti –to perform work.

By

implication, the Gunas other than the two described as the ultimate modes of Shakti or Energy, are also capable of actions, though to a limited extent. In other words, the physical qualities of substance, such for example as Pichchila, Sandra, Drava, Sthira etc., also perform actions by virtue of these qualities. The other significant clarifications offered by Hemadri which have a direct bearing on the subject now under study relate to Rasa, Guna, Vipaka and Virya. According to the description furnished by him ‘that evokes tasteperception is Rasa and all the rest are Gunas. Particular or distinct - Vishista rasa – or taste that occur as the result of Kayagnipaka is Vipaka and generated Guna at this stage is Virya. The scientific implications of these clarification are that there are two kinds of substances viz., those that evoke taste-perception and other that do not. Substances that belong to the former group, described after their Rasas or tastes, are six in number. Of them some are organic viz., sugars, facts (oils, ghee, marrow etc.,) and proteins and some that are inorganic viz., salts, acids, bases etc. substances that do not evoke taste perception are insipids. This grong is to be understood and characterized from the point of view of their of their Gunas such as Guru, Sandra, Vishada, Drava etc.

The

metabolites that occur in the course of Kayagnipaka are to be characterised in terms of terms of their resultant tastes or Rasas viz., Madhura (sweet) Amla (sour), and Katu (acrid, pungent) and not from the point of view of Basic concepts of Ayurvedic pharmacology 76

their Gunas. Virya, described as the capacity or the power to perform is actualized or released – Utpannaguna –by Kayagnipaka. Thus, while Madhura Vipaka is invariably associated with Shita Virya, Amla and Katu Vipakas are, likewise, associated with Ushna Virya. By the same token, the end products of Kayagnipaka characterized as Madhura Vipaka are to be expected to exhibit Guru, Snigdha, Mridu, and Shita Gunas. Similarly, the end-products of Kayagnipaka characterized as Amla Vipaka, are to be expected to exhibit Laghu, Snigdha and Ushna Gunas. Like wise, the end-proeucts of Kayagnipaka characterized as Katu Vipaka, are to be expected to exhibit Laghu, Ruksha, Tikshna, and Ushna Gunas. Of the intermediate metabolites that are Amla and Katu, the latter are considered to be relatively more powerful than the former. The Snigdha Guna of the former i.e., Amla kind of metabolites, is obviously responsible for the difference. The inter-relationship that is stated to exist among Virya, Guna and Rasa and of them, the uniqueness of Viryas has been stressed by Shivadasasena.

He observes: ‘Shakti is Virya.

performing powerful actions.

It alone is capable of

These actions do not suffer from any

limitation due to the non-attachment of Viryas to Rasas. Virya is intimately correlated to Gunas viz., Ushna, Shita etc. Since Virya inheres inseparablySamavya-in dravyas, it is considered to be complementary to Rasas. In regard to Rasas, described sometimes as principles of action, Arunadatta has stated that they are not stable because they undergo changes under the influnce of Jatharanala (Agni). Such is not the case with Gunas viz., Guru and the rest. Basic concepts of Ayurvedic pharmacology 77

That it is Virya which is responsible for making matter work is seen from the observations of Chakrapani Datta. He notes: ‘Virya is that which causes (matter) to perform work. Shivadasasena has observed that ‘Virya is a special power’. Hemadri has made a reference to the view that Viryas are many and observed that ‘though Virya has been described as two, it can still be as many as there are actions to be performed. In this view, all actions, regardless of Gunas, are due to Virya and, therefore there can be as many Viryas as there are actions. Emphasizing the view that Gunas are only modes of, Shakti, Charakapani Datta has observed that ‘by them “Ena (used by Charaka in the description of Virya viz., Viryam tu praya kriya is meant Rasa, Gun Vipaka, or Prabhava or Gunas, such as Guru etc., and Para etc., and, actions performed in terms of Tarpana, Prahladana, Shamana etc., Actions attributed to them are all spoken of as Virya.

The citations above are a few, among many such, found scattered in authoritative commentaries on the three major Ayurvedic classics, belong to periods anterior to A.D. 1200. These are sufficient to focus attention on some of the important physico-chemical or, better still, bio-chemical concepts basic, particularly, to the study of the metabolism of nutritional and medicinal substances described in Ayurveda.

The following principles

emerge from these citations:i. Virya is Samavaya in Dravya. This is the same as saying that energy inheres inseparably in matter. ii. Dravya and Virya are indestructible; they can neither be created nor destroyed. Matter/energy in the universe represent a quantitative, Basic concepts of Ayurvedic pharmacology 78

permanence. iii. Like Agni and Shoma or Prana and Anna of the universe, Ushna and Shita Viryas represent, at the microcosmic levels, specially at the biochemical levels-kinetic and potential energies. iv. Gunas or physical qualities/properties of substances are modes (or different manifestations, of Virya or energy. v. Ayurveda has described twenty Gunas comprising ten each of the opposites. These can be classified broadly under two Virya modes viz., Ushna and Shita, corresponding to kinetic and potential energies respectively. Of these eight comprising four each of the opposites have, on their own Merits, been designated as and classified broadly under the two main Virya categories, viz., Ushna and Shita. Considerable significance has been attached to these eight Gunas as they are decemed to be effective in the performance of actions. The remaining twelve Gunas, on the other hand, are considered to be incapable of performing actions. The remaining twelve Gunas, on the other hand, are considered to be incapable of performing actions on their own. A Virya status has, therefore, not been conferred on them. vi. The twelve Guna’s comprising six each of the opposites, are considered to be susceptible to changes in the course of digestive processes. These changes are held to reflect Pari Pasu changes in the Panchabhautic structure of the related Anus or elemental units, also known as Arambhakaparamaus. It is held that, similar is not be the case with the remaining eight Gunas which, by implication, are not affected by digestive processes. Basic concepts of Ayurvedic pharmacology 79

vii. Rasa or tastes of substances like Gunas, reflect specific modes of substances i.e., the Arambhaka Paramanus. They are considered to be extremely susceptible to changes both during the process of digestion as well as in the course of Kayagnipaka or metabolism. Rasas or tastes of substances are therefore not stable. viii. Vipaka of nutrient and medicinal substances, described in terms of the Rasas or tastes of the end products of Kayagnipaka viz., Madhura, Amla and Katu, reflect only the specific modes of the Panchabhautic structure of the elemental units of the ultimate metabolic products. These are the outcome of highly specialized reactions implied in Kayagnipaka. The Rasas or tastes in terms of which these endproducts have been described are the Vishishta Rasas.

Actions

performed by Vishishta Rasas are stated to be due to the release from the related Annus or molecules their Gunas or qualities/properties by Kayagnipaka

or

metabolic

reactions.

As

the

Gunas

or

qualities/properties, thus released, are efficient in the performance of actions, they are spoken of as Utpanna Gunas. The Utpanna Gunas are Ushna and Shita which, in the final analysis, represent two modes of Shakti/Virya or energy. ix. Rasas are not modes of Shakti/Virya. Shakti/Virya or energy is more intimately correlated to Gunas and, in particular, to Ushna and Shita Gunas.

Therefore Rasas, and Virya modalities may be mutually

complementary but not identical.

The former are destructible or

changeable, whereas, the latter which inhere inseperably in DravyaSamavaya are as indestructible as Dravyas are. Viryas are important modes of Dravyas. Rated at their best, Rasas can only signify the nature of particular modes of the Panchabhautic structure of the Basic concepts of Ayurvedic pharmacology 80

related Anuas or molecules. x. What really counts in all bio-chemical sequences are the twenty, eight and two Gunas-the latter two being treated as Viryas. The twenty Gunas, including the eight refer generally to a mixture or loose combination of different heterogeneous chemical compounds that occur in such mixtures in nature.

PRABHAVA Where there is similarity in two drugs in relation to their Rasa (taste), Vipaka and Virya (potency) but in spite of this similarity these two drugs differ with regard to their action, the distinctive feature responsible for their distinctive effects not supported by their taste, Vipaka and potency is regarded as ‘Prabhava’ or principle responsible for specific action. Both Chitraka (Plumbago zeylanica Linn.) and Danti (Baliospermum montanum) are pungent in taste as well as Vipaka and they are hot it potency. But in spite of this similarity, Danti (Baliospermum montanum) acts as a pungative while Chitraka does not. The purgative effect of Danti therefore, can be explained only by taking recourse to its Prabhava. The anti-toxic property of toxins, actions leading to the upward and/or downward elimination of Doshas and various effects of precious stones (Mani) when worn over the body - all these are due to their Prabhava which are beyond all plausible explanations. Vagbhata also quotes when the Rasa and others Gunas area of equal strength, that action is said to be arisen from Prabhava (for example); though Basic concepts of Ayurvedic pharmacology 81

Danti (Croton tiglium) is identical with Chitraka (Plumbago zeylanica) in (respect of) Rasa (taste) etc., it (Danti) is a purgative, (while Chitraka is not so); similarly so, are Madhuka (Glycerrhiza glabra) and Mridvika (Vitis vinifera), Mridvika is a purgative but Madhuka is not so; Ghrita (ghee, butter-fat) and Kshira (milk) in respect of kindling digestion (Ghrita kindles digestion where as Kshira does not). The various effects of the wearing of precious stones include antitoxic and anodyne actions. Besides, such of the properties of drugs like invigoration (Jivaniya) and promotion of memory (Medhya) manifest their therapeutic effects by virtue of their specific action. Chakrapani Dutt comments that “It may however, be argued that if Danti (Baliospermum montanum Muell Arg.) etc., manifest their purgative effects themselves why do they not manifest such actions when soaked in water? But this argument does not disprove the identity of active principles of the concerned drugs. Drugs manifest their specific action only so long as they are not overpowered by any other extraneous forces. In the example, cited above, soaking with water serves as the inhibiting Factor for the manifestation of the specific action.” The explanation of the Naiyayikas about the antitoxic properties of toxins, their mutually contradictory properties in the form of upward and downward movements of toxins also supports the above theory. That is to say according to them the downward moving property of the manifestation of such effects is due to Prabhava of both types of toxins.

Similarly the

purgative and emetic effects of drugs can be explained due to Prabhava based on the Mahabhautika composition of drugs.

Basic concepts of Ayurvedic pharmacology 82

Different action of drugs depending on the various factors may be illustrated as follows. Honey by virtue of its astringent taste alleviates Pitta, plants of Mahat Panchamula group (Aegle marmelos, Oroxylum indicum., Gmelina arborea., Sterospermum suaveolens., Clerodendrum phlomidis) inspite of their astringent and bitter tastes all elleviate Vata rather than Pitta because of their hot potency. unctuousness.

Honey again cures Kapha due to its

Inspite of its pungent taste Sunthi (Zingiber officinale)

alleviates Vata because of its sweet Vipaka. Inspite of its pungent taste and Vipaka and also hot potency Danti (Baliospermum montanum) serves as a laxative because of its Prabhava. Sushruta further quotes that “Drugs which have evident characters and effects and are popular by nature should never be subjected to debate as even by thousand arguments. Ambasthadi group of drugs can not cause purgation, hence the wise should stand by arguments through the scripture.”

Vichitra Pratyarabdha Dravya – (extraordinary substances) There is the special category (of substances) known as Vichitra Pratyayarabdha, (born out of peculiar combination of causative factors, i.e., the Panchabhutas), for example – both Godhuma (wheat) and Yava (barley) possess Swadu and Guru (sweet and heavy qualities) yet Godhuma (wheat) mitigates Vata whereas Yava (barley) aggravates (increases) Vata; fish is hot (in potency) while milk is cold (in potency) (though both are sweet and heavy), meat of lion though of sweet taste becomes Katu (in Vipaka) whereas the meat of the pig is not so (does not become pungent after digestion).

Basic concepts of Ayurvedic pharmacology 83

Mutual Relationship among Rasa – Virya – Vipaka – Prabhava: In case the Rasa, Vipaka, Virya and Prabhava are all of equal strength, by nature taste is superceded by Vipaka, both of them in turn are superceded by Virya and Prabhava overcomes all of them. For example, sweet taste of honey is overcome by its pungent Vipaka, that is to say, inspite of its sweetness honey does not aggravate Kapha. Both the Rasa and Vipaka of the meat of aquatic and marshy animals are sweet but the taste and Vipaka of the meat are overcome by its Ushya Virya with the result that it aggravates rather than alleviates Pitta. The taste and Vipaka of wine is sour and it is of hot potency. But inspite of this wine is considered as lactogenic due to its Prabhava. Similarly, in spite of its pungent taste and Vipaka, and also of its hot potency Danti (Baliospermum montanum Muell Arg.) acts as a purgative due to its inexplicit principle.

So taste, potency and Vipaka are all

superceded by Prabhava. Certain drugs manifest their action by virtue of their taste; some by virtue of their potency or other qualities, some by Vipaka (biotransformation or metabolism) and others by their Prabhava (causative principle for specific action). Some drug, when taken, pacifies or aggravates Dosha by its own (nature), some by Virya, some by Rasa and some by Vipaka. Dalhana further explains that Atmana means own nature (natural composition) as Parthiva, Apya, Taijasa, Vayavya and Akasiya, such as Khadira alleviates Kustha; Dosha in this context also denotes disease; Viryena – by potency two or eight types, this has already been explained in context of Mahat Panchamula etc; Rasavipakabhyam – by Rasa such as Basic concepts of Ayurvedic pharmacology 84

Guduchi, though Ushnavirya, pacifies Pitta due to bitter taste; by Vipaka such as Sunthi, though pungent, pacifies Vata due to Madhura Vipaka. There is no Paka without Virya, no Virya without Rasa and no Rasa without Dravya, hence Dravya is the chief of all. Dravya is the substratum in which Rasa etc. reside. Origin of Dravya and Rasa is interdependent like that of body and soul. The eight Gunas, designated as Virya, also reside in Dravya and not in Rasa as Gunas are said as devoid of Gunas (Guna can not reside in another Guna). Inside the body, Dravyas are digested and not six Rasas and as such Dravya is above all while other entities depend thereon.

Relative importance of Dravya and its Attributes

Dravya is dominant : Some scholars say - Dravya is the chief factor. Because of their fixed nature, Dravya is fixed and not Rasas, such as Rasas etc. which are present in unripe fruit do not continue in the ripe one; also due to constancy, Dravya is constant while Gunas are not such as preparations paste etc. of the drug undergo change in taste and smell, good or bad, (while the drug remains the same); also due to staying in own elemental group such as Dravya predominant in Prithvi does not shift to another group and so on; also because of being perceived by (all the) five sense organs; Dravya is perceived with a single sense organ like sound by ears and so on); also because of being substratum; Rasa etc. reside in Dravya; also due to Basic concepts of Ayurvedic pharmacology 85

capability of action, action depends on Dravya such as in ‘one should cook after collecting and crushing Vidarigandhadi drugs’ activity is centered on drugs and not taste etc,; also on scriptural testimony – scriptures mention drugs in formulations and not Rasas etc. such as Matulungaganimanthau ca etc,; due to dependence of Rasas etc. on the order of Dravya such as fresh in young, complete in fully mature; also due to usefulness of a part, diseases are treated by even a part of the Dravya such as by latex of Snuhi; hence Dravya is the chief and not Rasa etc. why? Because the latter have no parts. Dravyas is defined as – that which possesses action and property and is inherent cause (of the effect). Rasa is dominant: By sacred traditional knowledge which is known as scripture, therein Rasas are given important position such as ‘food depends or Rasas and therein are Prana (vital breath); also by injunction, Rasas are described such as sweet, sour and salty tastes pacify Vata; also by inference of the Madhura Dravya; also by seer’s words which are Vedas such as- ‘bring some sweet for the sacrifice’, hence Rasas are chief, Rasas are known as Gunas, characters of Rasas would be described elsewhere.

Virya is dominant: Virya (potency) is the chief, among the principles of drug action because the actions of drug depend on it. Drug action such as of emetic, purgative, both emetic and purgative, cleansing, pacifying, astringent, appetizer, pressing, decreasing body-weight, increasing body-weight, Rasayana, aphrodisiac, causing oedema, dissolving odema, burning, tearing, intoxicating, causing death, counteracting poison etc. take place due to supreme importance of Virya. Virya is of two types – cold and hot as universe is composed of Agni (fire) and soma (water); some take it of eight Basic concepts of Ayurvedic pharmacology 86

types-cold, hot, unctuous, non-unctuous, non-slimy, slimy, mild and sharp. These Viryas exert their action by subduing Rasa with eminence of their innate power or property; such as – Mahat Panchamula, though astringent in taste followed by bitter, pacifies Vata due to Ushna Virya; similarly, Kulattha and Palandu, though being (in taste) astringent and pungent respectively, pacify Vata also due to unctuousness (Snigdha Virya); sugarcane juice, though sweet, increases Vata due to Sita Virya; pungent Pippali pacifies Pitta due to mild and Sita Virya, similarly do sour Amalaka and rock salt. Kakamachi, though bitter increases Pitta due to Ushna Virya. Sour Kapittha pacifies Kapha due to Ruksha Virya, and also sweet honey acts in a similar way. Vajikaranam – aphrodisiac, it denotes both increase of semen and sexual potency; Adi after Visaprasamana includes wound-healing, repilation etc. ‘Pippali pacifies Pitta’ is the view of Viryavadins, but in fact, it does not do so; or the fresh and moist one pacifies Pitta while the dried one aggravate it; others, however, say like this – Viryavadin takes Kakamachi as Ushnavirya whereas the teacher accepts it as moderate, neither too hot nor too cold, that is why Kakamachi pacifies all the three Dosha; Mulaka here is mature and bigger one and not the tender one which pacifies three Doshas. If Rasas which normally pacify Vata are endowed with roughness, lightness and coldness, they do not do so; if Rasas which are Pitta – pacifying are endowed with sharpness, hotness and lightness they do not exert that action; if Kapha – pacifying Rasas are endowed with unctuousness, heaviness and coldness they do not exert that action. Hence Virya is the chief.

Basic concepts of Ayurvedic pharmacology 87

Vipaka is dominant: Susruta while discussing the importance of Vipaka Quotes “Because of digestive transformation being appropriate or faulty; all substances when ingested undergo appropriate or faulty digestive transformation producing wholesome or unwholesome effects respectively. Here others say that every Rasa has its own Paka; some, however, hold (Vipaka) as of three types – sweet, sour and pungent; this is not correct; according to properties of Bhutas (primal elements) and scripture, there is no other Vipaka as sour because sourness comes to Pitta when it gets half – burnt due to igneous nature, if this is accepted as a Vipaka, salty taste would also claim to be a Vipaka as Kapha, when half-burnt, gets salty taste. Some say that Vipaka is similar to Rasa such as Madhura Vipaka of sweet, Amla of sour and so on; further they support it with the following examples – milk boiled in a utensil stays finally as sweet only, likewise, paddy, barley, green gram etc. sown in the field do not get away from their nature even at the terminal point, this is also like that. Some, however, maintain that weaker ones are subdued by the stronger ones, but as it would create uncertainty, it is unprincipled. In scripture, only two Pakas are there-Madhura and Katu also known as Guru and Laghu respectively; the five Mahabhutas may be grouped into two on the basis of similarity in properties e.g. Guru and Laghu. Prithvi and ap are Guru while others are Laghu. Hence there are verily two types of Paka”

Basic concepts of Ayurvedic pharmacology 88

2. ESSENTIAL COMPONENTS OF DRUG EVALUATION DESHA (LAND/LOCALITY) The drugs become capable of producing maximum therapeutic effects when their potency augmented by Desha-Sampat (collecting the plants from the appropriate habitat), Kala-Sampat (collecting these plants in the appropriate season), Guna-Sampat (collecting plants when these are enriched with excellent attributes) and Bhajana-Sampat (strong these plants in appropriate containers).

Habits (Desha) are of three types, viz., Jangala (dry land), Anupa (marshy land) and Sadharana (normal land.)

The Jangala Desha (dry land) is characterized as follows: 1. It abounds in open sky; 2. It has deep forests of trees like Kadara, Khadira, Asana, AsvaKarna, Dhava, Tinisa, Sallaki, Sala, Somavalka, Badari, Tinduka, Asvattha, Vata and Amalaki; 3. It is mostly surrounded by trees of Sami, Kakubha and Simsapa in large number; 4. The tender branches of these trees dance, being swayed by the force of continuous dry wind; 5. It abounds in thin, dry and rough sands as well as gravels which gives rise to mirages; 6. This area is inhabited by Lava, Tittiri and Chakora birds; and 7. The people inhabiting this type of land are dominated by Vayu Basic concepts of Ayurvedic pharmacology 89

and Pitta, and most of them are sturdy and hardy.

The Anupa Desha (marshy land) is characterized as follows: 0. It contains deep forests of trees like Hintala, Tamala, Narikela and Kadali; 1. It is located generally at the banks of rivers and sea; 2. Mostly cold wind blows here; 3. This type of land is located in the neighbourhood of rivers whose banks are beautified by plants like Vanjula and Vanira; 4. It has mountains covered with beautiful creepers; 5. The trees in this thick forest wave with the gentle breeze; 6. The area is surrounded by thick forests with beautiful and blossoming trees; 7. It is covered with tender branches of trees; 8. The branches of trees located here are echoed with the sound produced by birds like Hamsa, Chakravaka, Bhringaraja, Satapatra and inebriated Kokila; and 9. People inhabiting this type of land are of tender body, and generally they are dominated by Vayu and Kapha.

The Sadharana-Desha (normal land) is characterized as follows: 1. It has creepers, Vanaspati (trees having fruits without apparent flowers), Vanaspatya (trees having both flowers and fruits); and 2. Persons inhabiting this land are study, tender, endowed with strength, complexion and compactness, as well as other attributes of people inhabiting in the land of general nature. Medicinal plants, for producing excellent therapeutic effects, should Basic concepts of Ayurvedic pharmacology 90

be colleted from places having the following characteristic features: 1. These are to be collected from Sadharana-Desa (forests of normal land) or Jangala-Desa (dry land forest); 2. Plants should have been exposed to seasonal cold, sun, wind and rain appropriately; 3. Plants should have grown over plains and clean land surrounded by water reservoirs; 4. Plants should not have been grown in a crematorium, Chaitya (sacred tomb), prayer ground, assembly ground, pits, parks, anthills and saline soil; 5. The land should have enormous growth of Kusa and Rohisa; 6. The soil should be unctuous, black in colour and sweet in taste or golden yellow in colour and sweet in taste; and 7. The land should have been ploughed, and there should not be other big trees in the vicinity over-shadowing the medicinal plants.

Period of Collection of Drug: Drugs should be collected in the appropriate season when they have attained maturity in respect of their size, taste, potency and smell. Their smell, colour, taste, touch and Prabhava (specific action) should have remained unaffected by Kala (time, viz., over-maturity), excessive exposure to sunrays, fire, water and wind, and by parasites. They should be endowed with all attributes. They should be collected from the northern side Fresh branches and tender leaves should be culled in the rainy season and spring. The roots should be collected in summer or late winter (Sisira) Basic concepts of Ayurvedic pharmacology 91

when the leaves of the trees have ripened and spring. Their Sara (heart-wood including exudates) should be collected in Hemanta (early winter). Flowers and fruits should be collected during appropriate seasons when flowers and fruits appear in the plant. One should collect the various parts of these plants i)

facing towards the east or north

ii)

after performing auspicious rites in a spirit of compassion,

iii)

living a pure life and to wear white dress,

iv)

after offering prayers to the gods, Asvins, cows and Brahmins, and

v)

observing fasting on previous day.

The collected plant products should be kept in appropriate containers well covered with lid, and hung on a swing. The storeroom should have doors facing towards the east or the north. The room should have only one window for ventilation. Flower – offerings and sacrificial rituals should be carried out. The drug and store hence should be hazards of fire, water, moisture, smoke, dust, mice and quadrupeds.

COLLECTION OF DRUGS: The ideal drug should have grown in commendable place, have been taken out on auspicious day, be in proper dose, agreeable; with desired smell, colour and taste; able to alleviate the disorder, non-toxic, harmless on faculty use, administered after proper examination and in time.

Basic concepts of Ayurvedic pharmacology 92

While taking up the management of the patient, the physician should examine the life-span verily in the beginning, if it is on positive side, then he should examine disease, season, Agni, age, physical strength, mental strength, suitability, constitution, drug and place. Sushruta quotes the contemporaray scholar’s view that root, leaf, bark, latex, heart-wood and fruit should be collected in early rains, rainy season, autumn, early winter, spring and summer (seasons) respectively, but he states it as incorrect. According to

Saumya (watery) and Agneya

(igneous) nature of universe; (in fact), Saumya plants should be collected in Saumya seasons while Agneya in Agneya ones, thus their properties are not affected. Saumya plants grown in land predominant in qualities of soma and collected in Saumya seasons are extremely sweet, unctuous and cold. Saumya season - Rainy season, early winter and late winter; Agneyaautumn (Sarat), spring (Vasanta) and summer (Grishma). In emergency, forenoon may represent spring and so on, Agneya plants grown in Agneya land and collected in Agneya seasons are extremely pungent, rough and hot. Purgative drugs should be collected which are grown in land predominant in qualities of Prithvi and Ap; emetics may be taken from the land predominant in Agni, Akasa and Vayu; drugs with dual action (emetic as well as purgative) from the land having properties of both; pacifying (Samsamani) drugs should be taken from the land with predominance of the qualities of Akasa. In this way, they become more potent. With regard to formulations such as Patralavana etc. which is composed of all parts (of the plant), no time is fixed and as such collection of Basic concepts of Ayurvedic pharmacology 93

drugs may be done in all seasons. All drugs are verily more potent when fresh, except honey, ghee, Jaggery, Pippali and Vidanga. Vidanga, Pippali, honey and ghee – these are wholesome when old, other drugs should be taken fresh and free from defects. All verily with latex (sap) are potent. If these (honey etc.) are not available in very old state, those of beyond one year should be taken.

Collection of Animal Products: Blood, hairs, nails etc. should be collected from adult animals. Milk, urine and feaces should be collected after food is digested.

Potentiation of Drug Action: In addition to adding to the potency of the recipe, it is necessary to impregnate the ingredients of a recipe with the juice or decoction of other drugs.

When properly impregnated even a small quantity of the drug

becomes exceedingly effective. Therefore, ingredients of a recipe should be impregnated with the juice or decoction of other ingredients having identical potency. By virtue of appropriate Samyoga (addition of ingredients), Vislesha (elimination of ingredients), Kala (appropriate time of administration) and Samskara (processing) even a small quantity of a drug may produce more powerful effects, and otherwise even a recipe in large quantity may produce very mild effects. If a drug is added with ingredients having identical potency, then the effect of the recipe taken even in small quantity becomes more powerful. Similarly, if a drug is added with ingredients having opposite potency then Basic concepts of Ayurvedic pharmacology 94

the effect of the recipe taken even in large quantity becomes milder. In certain cases, the milder effect of the recipe is necessary in order to make it suitable to the requirement of the nature of Koshtha (nature of bowel). In the same way, the effects of Vislesha (elimination of ingredients), Kala (time of administration) and Samskara (processing) can be explained and illustrated.

The following factors are responsible for increasing the strength of a recipe: 1. The ingredients are not impaired by exposure to water, fire and insects; 2. The ingredients are imbibed with the beneficial attributes of the soil and season; 3. The recipe is administered in a slightly higher dose; 4. The ingredients are appropriately impregnated with drugs having similar potency; and 5. The patient is administered oleation and fomentation therapies.

Sahayoga (Adjuvants): Different adjuvants are required to be used along with these drugs in accordance with the Doshas involved in the causation of the disease. These drugs should be impregnated and mixed with Sura, Sauviraka, Tusodaka, Maireyaka, Medaka, Dhanyamla, Phalamla (juice of sour fruits like pomegranate), Dadhyamla (sour yoghurt), etc., for the treatment of diseases caused by Vayu. For the treatment of diseases caused by Pitta, these drugs are to be used by adding Mridvika, Amalaka, Madhu (honey), Madhuka, Parusaka, Phanita, milk, etc. For the treatment of diseases caused by Kapha, Basic concepts of Ayurvedic pharmacology 95

these recipes are to be added with Madhu (honey), Mutra (urine), Kashaya (decoctions of Kapha-alleviating drugs), etc. In different recipes, alcohol, etc., are added as constituents, vehicle or expicients to the main drugs like Madana-Phala. In these recipes, MadanaPhala, etc., are the main ingredients, and alcohol, etc., play only a secondary role. Therefore, these recipes are named after the principal ingredients, and not after the ingredients like alcohol, however, follow the effects of the principal drugs used in the recipe. Some times the drugs of secondary nature have antagonistic potency. Even then they do not contradict the effects of the principal drug. If these drugs of secondary nature are similar in potency as that of the principal drugs, then the recipe becomes all the more effective therapeutically. Principal drugs like Danti, etc., have strong action, and meat-soup, etc., added to the recipes of Danti are mild in action. Ela, etc., which are cardiac may reduce the emetic effect. Combination of these drugs having opposite potency, however, does not affect the effects of the principal ingredient. On the other hand, not with standing their opposite potency, they actually help emetic and purgative effects of the principal ingredient. If the drugs of secondary nature have the potency similar to that of the principal drug, then obviously the effect of the compound recipe becomes all the more potent. Drugs of antagonistic potency are added to a recipe in order to impart desirable colour, taste, touch and smell.

Such addition also helps to

effectively cure the diseases. Basic concepts of Ayurvedic pharmacology 96

Emetic and purgative recipes (therapies) are administered for the treatment of several diseases. But the disease cannot be fully cured simply by emesis or purgation. Therefore, in emetic and purgative recipes, some other drugs (Even those having opposite potencies) are added so that the recipe as a whole becomes effective to cure the disease.

Time of Administration of the Drug (Bheshaja Kala) All the medicines are generally administered in the morning and Kashayas (decoctions) are administered specifically during this time. Vagbhata has delineated the following details regarding Oushadha Kala (time of administration of drugs) 1. Abhakta (without food)

-

Kapha dominancy and in strong

-

Diseases of Apana Vata, Lower

persons 2. Pragbhakta (before food) extremities and obesity 3. Madhyabhakata (during meal)-

Diseases

of

Samana

Vata,

Pittaja Dosha and elementary tract 4. Adhobhakta (after meal)

-

Diseases of Vyana Vata (after

midday meal) Diseases of Udana Vata (after night meal) Diseases of Urdhwanga and Krisatwa (emaciation) 5. Sabhakta (mixed with food) -

Children, Delicate and persons

with aversion

Basic concepts of Ayurvedic pharmacology 97

towards the medicine, diseases affecting all over the body 6. Antarbhakta (in between meal)-

Vyana Vata disorders

7. Samudga (at the commencement and end of the meal) – Hiccup, Kampavata, Convulsions, 8. Muhurmuhu (frequent administration) – Swasa, Kasa, Hiccup, Trishna, Chardi, Visha 9. Sagrasa (mixed along with one morsel) – Disorders of Prana Vata 10. Grasantara (in between the morsels)- Disorders of Prana Vata 11. Nisi (bed time) 

-

Urdhwajatrugata Roga

Sarangadhara has suggested the following Oushadha Kalas 

After Sunrise



At the time of midday meal



At the time of night meal



Frequent intervals



Bed time

Dosage of Medicine (Oushadha Matra) 

During the first month of life of the baby, given the dose of medicine to be administered should be one Raktika (125mg) given with milk, honey, sugar or ghee.



With each succeeding month the dose should be increased by one Ratti, till the first year when the dose will be One Masha.



Further increase will be one Masha for each successive year till the age of sixteen years Basic concepts of Ayurvedic pharmacology 98



For 16 to 70 years the dose should be the same.



After 70 years it has to be gradually reduced as was the case with children.



This is the dosage for Kalka (bolus), and Churna (powders), while for Kashayas (decoctions) it is to be administered four fold to the described dosage.

Mana (Weights & Measures): The table of weights and measures used in Ayurveda is as follows: (The basic weight is Dhvamsi which is also called Trasarenu. According to some physicians, it is also called Dhuli or a floating dust particle.) a. 6 Dhvamsis make one Marichi; b. 6 Maricis make one (Rakta) Sarsapa (lit. red mustard seed); c. 8 Rakta – Sarsapas make one Tandula (lit. grain of rice); d. 2 Tandulas make one Dhanya – Masa (lit. black gram); e. 2 Dhanya – Masas make one Yava (lit. grain of barley); f. 4 Yavas make one Andika; g. 4 Andikas make one Masaka (Masa); [It is equivalent to 1 gram]; its synonyms are Hema and Dhanyaka; h. 3 Masas make one Sana; (It is equivalent to 3 grams); i. 2 Sanas make one Dranksana; (It is equivalent to 6 grams); its synonyms are Kola and Badara; j. 2 Dranksanas make one Karsa; (It is equivalent to 12 grams); its synonyms are Suvarana, Aksa, Bidala – Padaka, Picu, Pani – Tala, Tinduka and Kavala - Graha k. 2 Suvarnas (Karsas) make one Palardha, i.e. half Pala; (It is Basic concepts of Ayurvedic pharmacology 99

equivalent to 24 grams; its synonyms are Sukti and Astamika; l. 2 Palardhas make one Pala; (It is equivalent to 48 grams); its synonyms are Musti, Prakuncha, Chaturthika, Bilva, Sodasika and Amra; m. 2 Palas make one Prasrita; (It is equivalent to 96 grams); Its synonyms is Astamana; n. 4 Palas make one Anjali; (It is equivalent to 192 grams); Its synonyms is Kudava; o. 2 Kudavas make one Manika; (It is equivalent to 384 grams); p. 4 Kudavas make one Prastha; (It is equivalent to 786 grams); q. 4 Prasthas make one Adhaka; (It is equivalent to 3.072 kilograms); r. 2 Adhakas (8 Prasthas) make one Kamsa; (It is equivalent to 6.144 kilograms); s. 4 Kamsas make one Drona; (It is equivalent to 24.576 kilograms); Its synonyms are Armana, Nalvana, Kalasa, Ghata and Unmana; t. 2 Dronas make one Surpa; (It is equivalent to 49.152 kilograms); its synonym is Kumbha; u. 2 Surpas make one Goni; (It is equivalent to 98.304 kilograms); Its synonyms are Khari and Bhara; v. 32 Surpas make one Vaha; (It is equivalent to 1572.864 kilograms); and w. 100 Palas make one Tulaa; (It is equivalent to 4.800 kilograms). The above mentioned weights and measures are applicable to dried articles of drugs and food ingredients. The above mentioned weights and measures, according to Dridhabala, belong to Magadha-Mana (those prevalent in the country of Basic concepts of Ayurvedic pharmacology100

Magadha). Another popularly used unit of weight is Ratti (fruit of Abrus precatorious). According to Magadha tradition, ten Rattis constitute one Masa (gram). According to Susruta, who follows the weights and measures of Kalinga tradition, five Rattis constitute one Masa. In addition to the above, other units of weight like Valla which is equal to three Rattis are also described in text.

The Pharmacopoeia

Committee has found out 125mg. as equal to one Ratti or Gunja. In the Ayurvedic classics linear measurements like Angula (3/4 of an inch), Vitasti (9 inches) and Hasta (18 inches) are also mentioned. Drug, either new or old, should be accepted only when it is unaffected with bad smell and undamaged in terms of taste etc.

Drug Store House (Place of preservation): Store-room should be in auspicious quarters and in clean surroundings where drugs may be kept in cloth-bags, earthenware, wooden planks and nails.

Viruddhahara (Food Incompatibility): The drugs and diets which are unwholesome for the normal Dhatus (tissue elements) and Doshas of the body, are in fact oppose the proper growth of such tissue elements and Doshas; Viruddhahara is classified such as 1. Some act due to their mutually contradictory qualities; 2. Some by combination; 3. Some by the method of preparation; 4. Some by virtue of the place (land and body), time and dose and 5. Some others by their (inherent) nature. Basic concepts of Ayurvedic pharmacology101

Some

substances

are

unwholesome

contradictory qualities; e.g. fish and milk.

due

to

their

mutually

Ripe Likucha (Artocarpus

lakoocha.) and soup of Masa (Phaselous radiatus) are unwholesome when taken in combination.

The difference between the drugs that are

unwholesome due to mutually contradictory qualities and those in combination is that the drugs of the former category are essentially those which possess mutually contradictory qualities while those of the latter category are unwholesome simply by their combination, irrespective of their qualities. The unwholesomeness of the drugs and diets possessing mutually contradictory qualities is mostly due to their Prabhava.

So inspite of

apparent contradiction in sweet and sour tastes or cold and hot potencies, the combination of all drugs and diets possessing these properties need not always be regarded as unwholesome. The meat of Kapota (pigeon) fried in mustard oil is unwholesome due to the method of preparation. Ashes and dust are responsible for causing unwholesomeness in drugs and diets.

Similarly, honey is unwholesome

when used by a person whose body is afflicted with heat.

Kakamachi

(Solanum nigrum Linn.) when staled, that is kept for some days, may cause death of the animal. Substances that are against any particular Dosha or bodily constitution are also to be included in the 4th category. Some drugs and diets are unwholesome by nature, e.g. poison (venom). All drugs and diets which dislodge the various Doshas but do not expel them out of the body are to be regarded as unwholesome.

Basic concepts of Ayurvedic pharmacology102

Anupana: Post-prandial drinks in general, bring about refreshment, pleasure, energy, nourishment, satisfaction and steadiness in the food eaten. It helps in breakdown, softening, digesting, proper assimilation and instant diffusion of the food / drug taken.

Basic concepts of Ayurvedic pharmacology103

3. VIRYA – AN IMPORTANT ATTRIBUTE OF DRUG ACTION In the context of drug action, the word Virya, as envisaged in the Ayurvedic classics by the ancient Acharyas, connotes different meanings in different contexts and ultimately projects factor of any drug by virtue of which it performs certain actions in the body. This comprehensive term is employed to explain lesser or greater potential factors in the drug in relation to different processes and procedures to achieve a desired effect in the body. Many phenomena may lead to one effect and many effects can be caused by one single phenomenon.

In view of this it becomes imperative to

discriminate different processes vis-à-vis different actions. These processes or phenomena, again involve certain body humors in different body tissues and, thereby, causing certain local and systemic actions all culminating into the main action of the drug. It is with special reference to the site and disease where in the drug mainly acts, one can conveniently prefer to call it the main action of the drug.

But each and every step of the entire

phenomenon of drug action should be taken into account before evaluating the proper drug action. Obviously, the term ‘Virya’ had to be used in the general actions of drug as well as the particular actions of the drug. It is, however, agreed and accepted that the general and particular actions of the drug are complementary and supplementary to each other in so far as the total effect of drug is concerned. Actions bigger or smaller, therapeutic or otherwise, can only be explained on the principles of structure – function relationship in the drug and preference may ofcourse, be given to the main therapeutic action of the drug. If functions without potency is inconceivable,

Basic concepts of Ayurvedic pharmacology104

the single connotation of Virya is illogical. This is the main reason why the word Virya has been used in a general and also in a specific sense. The Ayurvedic principles of drug action have been described in the form of Rasa, Guna, Virya, Vipaka and Prabhava. If these are the principles through which the drug operates, the word ‘Virya’, then, should also be used for actions of Rasa, Vipaka, Guna and Prabhava. As Prabhava could not be rationally and practically proved it was put into the category of empirical treatment and as the other four could be rationally and practically demonstrated they were put into another group. Right in the beginning Virya was divided into two groups Chintya Virya and Achintya Virya –chintya Virya indicating Virya in general and Achintya Virya indicating Prabhava. One who in trying to evaluate and understand the rationale behind these principles Prabhava should be excluded from the consideration.

The

remaining four are Chintya Viryas and, therefore, the relationship of Rasa, Vipaka, Guna and Virya with the general or specific actions of the drug should be understood. In simpler words ‘Virya’ will imply a specific factor in the drug which may be responsible for its therapeutic action and also other factors in the drug to understood by the terms Rasa, Guna, Vipaka and Virya, which may imply the general actions of the drug. This is how the face value of all the literature about the concept of Virya leads one to the above postulation. But, then, instances are found wherein the main actions of the drugs intended to be achieved in a particular disease – condition becomes explainable on the basis of Rasa, Vipaka and Guna only. In such a case, should the terms Rasa, Guna, Vipaka be used as Virya or else these very terms should be retained to explain their actions?

At this juncture our

attention is drawn to the following virgins described by Charaka.

Basic concepts of Ayurvedic pharmacology105

1. Certain drugs manifest their action by virtue of their taste; some by virtue of their potency or other qualities; some by Vipaka and others by their Prabhava. 2. Virya can be determined while in association with body (Adhivasa) or even immediately after coming into contact with the body (Nipata). 3. It is not that the various drugs and diets act only by virtue of their qualities. In fact they act by virtue of their own nature or qualities or both on a proper occasion in a given location, in appropriate condition and situations; the effect so produced is considered to be their action (Karma); the factor responsible for the manifestation of the effect is known as Virya; where they act is the Adhishtana (location); when they act is time (Kala); how they act is upaya (mode of action); what they accomplish is the achievement (Phala). Studying all the three versions together one is constrained to conclude that the whole rationality of drug action has been explained in terms of structure – function relationship with reference to the special affinity for a particular site of drug action. If this be so the Dravya along with its Rasa goes to explain the chemical constitution, Vipaka goes to explain the changes in chemical constitution, of drug right from digestion to metabolism. The changes that take place in the drug during the metabolism are explained in terms of Gunas and desired chemical constitution intended to achieve the desired therapeutic action is understood as Virya. It is true that the substance has a dominating position in the whole phenomenon as the qualities and actions are inherent in it (Samavayi)but , the actions of substances find expression through qualities (Guna) only. This is the main reason why the actions of Rasa, Vipaka or Virya had been explained by Basic concepts of Ayurvedic pharmacology106

using certain terms which fall in the categories of Guna. This whole picture definitely requires to be elaborately described on logical grounds, cause and effect relationship, constitution and the rationality behind it. In the coming pages an attempt has been made to make a theoretical thread – bare analysis of different aspects of Virya in relation to different constitution and actions of the drug. And an attempt will also be made to be made to pin point the site of action and jurisdiction of these terms. The Samprapti Vighatana being the Sunnum bonnum of the treatment and Shadupakramas being the therapeutic generalization of treatment will also be incorporated in this study of Virya, and a relationship among these will be established as and how befitting to the easy understanding of the concept of Virya.

RASA VIS A VIS THE CHEMICAL CONSTITUTION OF A DRUG IN RELATION TO IT’S ACTION All the substances in the world, whether they are animate or inanimate, are composed of the five proto elements and the relationship between the substances in the body and outside in the world is established on the basis of similar or dissimilar qualities of these five proto – elements. Vegetation is the first start of life for our purpose and the vegetable drugs contain specific types of arrangement of the five proto – elements giving rise to one specific and predominant taste. The knowledge of any kind is perceived by the senses and since the basic composition of Pinda and Brahmanda is based on the five proto elements, nature has provided us with five sense organs with a specific mission of knowledge relating to each of the five proto elements. The tongue is the sense organ for the perception of the Basic concepts of Ayurvedic pharmacology107

taste and hence the dictum – RASO NIPATAE DRAVYANAM. This is a practical knowledge. But the specific two protoelements combined in a specific manner to originate a specific Rasa is a question of inference. This inference is later practically substantiated by the action of those proto elements in the body. The permutation and combination of the five proto elements along with its innumerable yet controlled configuration can give rise to only six Rasas. On the other way round, only the six tastes can be perceived by the tongue and, therefore, for all practical purposes we have understood the combinations and configuration of the five proto elements in six types only. Whatever be the truth the fact remains that the super structure of the drug action is constructed on the infrastructure of the arrangement of these five proto elements in a drug. The perception of taste relates to the chemical stimulation of the tongue and since the taste arises out of the specific combination of the two predominant protoelements in a drug, one can safely and conveniently call it the chemical structure of the drug. Ultimately the components of the drugs in relation to its chemical reaction in and outside the body is understood in terms of chemical structure. The ancient Acharyas were fully justified in attaching prime importance to the six Rasas in relation to their structure paripasu their therapeutic action. The latest knowledge of drug chemistry has revealed one fact beyond doubt that there is structure –function relationship and the function, in a majority of cases, should be in accordance with the structure of the drug. To explain this point the ancient Acharyas ascribed three Gunas to each Rasa. The basic idea behind explaining the actions of Rasa on the basis of their Gunas is to indicate a structure – function relationship, structure –Rasa Basic concepts of Ayurvedic pharmacology108

representing the chemistry of the drug and the Guna representing the function of the drug. The Rasas are also Gunas, and Gunas cannot be depending upon another Gunas. However, each Rasa has been described to have three Gunas. The idea was to emphasise structure –function relationship. It is an established scientific fact today that drugs having similar chemical structure may have different properties and vice versa is also true. The ancient Acharyas took an account of this fact and ascribed these peculiarities to sudden, discrete or distinct attributes in the drug structure. This is why the concept of Vipaka came up. Confining ourselves to Rasa, we are constrained to locate the area or the site where the drug actions could be explainable on the basis of Rasa.

We know for certain that after

deglutition the drug or diet is subjected to digestive phases and that is the jurisdiction of Vipaka. The site or area of the actions of rasas, therefore, limited to the tongue, palate or oesophagus. In simpler words the actions of Rasa are more general and less systematic.

These general actions may

reflexly stimulate some organs in the uttamanga and this can be seen in the description of actions of each Rasa. Now let us remind ourselves of the general scope of Virya in which any action anywhere in the body is included in Virya and in Asthavidha Virya Vada the words Mrudu –Tikshana have also been used as Virya. The perception of taste is an electro chemical phenomena depending upon the capacity of the drug to stimulate specific taste buds and is ultimately the wave length which determines a particular Rasa. The saumya and Agneya classification of drugs in relation to the saumya and Agneya protoelemental components of the drug indicate that the Agneya drugs corresponding to Lavana, Amala, katu Rasas have higher wave length while the rest have the smaller wave length. This is why, even though the structure – function Basic concepts of Ayurvedic pharmacology109

relationship

with

reference

to

drug

chemistry

encompassed

five

protoelements resulting in to six Rasa, the actions have been simply explained by Mrudu – Tikshana Viryas.

Thus the Rasas indicate the

chemical structures of the drug and their functions have been ultimately explained in the form of Mrudu, Tikshna Virya. In order to be more specific, we would here after use these words – Mrudu, Tikshna –for the local actions caused by Rasas.

VIPAKA VIS A VIS DRUG METABOLISM IN RELATION TO DRUG ACTION The significant role of Agni in relation to digestion and metabolism has been explicitly described in Ayurveda.

All the substances whether

dietetic or medicinal are ingested so as to make them assimilable after proper digestion. The medicines are broken down and resynthesized during the process of digestion and metabolism. The resynthesis may be in the original form of the drug or otherwise. This is why the question of Samanapratyayarabdha and Vichitrapratyayarabdha find relevance to Vipaka. The site and area of Vipaka extend from Koshta to the Dhatus. Unlike the Rasa, the actions of Vipaka are to be taken in to account (Vipaka Karma Nishtaya) and the site of these actions have been described to be at the level of Koshta or at the level of the Dhatus. But then, again, the actions generally ascribed to the Vipakas are explained on the basis of Gunas only. Let us remind ourselves of the same situation with the rasas also. If the actions of Vipaka are to be explained at the level of Koshta, it is the Snigdha – Ruksha qualities which play their part and this is why Madhura and Amla Vipakas are said to induce smooth evacuation of stool and urine while the Katu Vipaka does the reverse. But when the actions of Vipaka are to be Basic concepts of Ayurvedic pharmacology110

explained at the level of the Dhatus, Guru & Laghu qualities play their part and this is why Madhura Vipaka increases the Dhatus while Amla and Katu Vipakas reduce them. This shows that either due to the change of site or the body element, or change in the chemical constitutions in the drug, different qualities come into action at different places. Looking at this whole from the angle of Virya, the Ashtavida Viryavada includes Snigdha –Ruksha qualities which go to explain the action of Vipaka at the Koshta level. One is reminded here of the version about the Virya which reads Viryam Yavat Adhivasat Nipatat Cha Upalabhyatae. The word ‘Nipata’ is related to Rasa on one side and the Virya on the other. Similarly the word ‘Adhivas’ is related to Vipaka on one side and the Virya on the other and, therefore, the words falling in the jurisdiction of qualities have been used to explain the actions of Rasa and Vipaka. These same qualities have been included in Ashtavidha Viryavada. The idea behind this is probably to explain the structure – function relationship with reference to the specific site of action and special affinity to a particular body element. If we are asked to fix up limitations and jurisdictions of these terms we would prefer to use the word ‘Rasa’ for its chemical structure causing certain local actions at the level of the tongue by virtue of Mrudu –Tikshna Viryas; and the ‘Vipaka’ to indicate the changes in the chemical structure of the drug in the digestive and metabolic processes and to confine the actions of Vipaka in the Koshta only so as to explain them with Snigdha – Ruksha Viryas. After the drug is absorbed it has to be picked up by the receptors in the specific body element or Dhatus on the qualitative similarity and, therefore, we would prefer to correlate other actions on the Dhatus with Gunas as enumerated in Rasapanchak.

Basic concepts of Ayurvedic pharmacology111

GUNA VIS A VIS DRUG ACTION There is no doubt about the fact that in the ultimate analysis the stimulation or depression corresponding to Vriddhi and Kshaya of the Dhatus are the two main resultant states after the drug administration. In fact in a general summary the actions have been divided in to Vriddhi and Kshaya only. The comprehensive and critical analysis of the stages of pathogenesis and the events envolved in them very clearly indicate that the Doshas are generally brought down to normal while the Dhatus are generally pulled up to normal. This is because of the fact that on a very general observation it has been proved that the Dosha Vrinddhi and Dhatu Kshaya are the resultant states of the disease –causing conditions. In view of this Ayurvedic medicine, generally speaking, depresses the Doshas and stimulates the Dhatus only in abnormal conditions. The Vriddhi and Kshaya can better be appreciated qualitatively rather than quantitatively. Let us postulate a view here that the structure – function relationship, in ayurvedic paralance, indicate the inheritance of the permanent qualities of the components. In view of this there should have been only two qualities ascribed to each Rasa, for only two predominant proto elements constitute one Rasa. But the texts have ascribed three qualities to one Rasa. The idea behind it is that the specific combination of the two proto elements originating a specific Rasa carry with them individual qualities as well as engender a specific quality also. This specific quality is of biological significance as the biotransformation in relation to the stimulation and depression of the body element relates to the third quality engendered by the combination of the two specific elements in Rasa. Obviously the Madhura Vipaka is said to be Guru while Amla and Katu Vipaka are said to be Laghu and their actions at Dhatu level are explainable on the basis of these two Basic concepts of Ayurvedic pharmacology112

qualities. It is, therefore, postulated that the words Guru and Laghu fall under the jurisdiction of Gunas as enumerated in the Rasapanchak. Since the comprehensive term Virya includes all actions at all levels the Guru and Laghu finds Place in Ashtavidha Virya vada. Each Dhatu is endowed with its specific Agni and the drug is treated with these Agnis before it exerts the influence on the Dhatus. This is what is mean by ‘Yatra Kurvanti tat Adhikaranam’. If the Vriddhi and Kshaya are to be explained on the basis of similars and dissimilars the biotransformation of the substances by concerned Dhatwagnis becomes imperative.

So far, from the point of view of

comprehensive term Virya a relationship is established between Rasa and Mrudu – Tikshna Virya, Vipaka and Snigdha – Ruksha Virya, Guna and Guru – Laghu virya and this completes six Viryas included in Ashtavidha Viryavada. The remaining two Viryas I.e. Sheeta and Ushna demand a special mention and clarification.

VIRYA VIS – A – VIS SPECIFIC THERAPEUTIC ACTION IN RELATION TO SPECIFIC SITE OF ACTION The diseases are to be cured or mitigated by the administration of certain of drugs which may have high therapeutic value. A cursory glance at the different processes of pathogenesis culminating into the manifestation of disease leads us to accept the prime significance of the role of the Srotamsi in causation of a disease. It is the state of manifestation (Vyakti) of samprapti in which cardinal symptoms of the disease are produced and these cardinal symptoms are, in one way or the other, related to one or other type of Srotodushti. This is just mentioned here to emphasize the important role of Srotodushti in a disease – condition. If the language of biochemistry is used the disease is the outcome of Dosha – Dushya Samoorchana (Interaction Basic concepts of Ayurvedic pharmacology113

between the vitiated Doshas and Dushyas ). This interaction is of two types. (1) Interaction between abnormally increased or decreased Doshas and Dushyas.

This is called Prakruti Sama Samaveta Samoorchana.

(2)

Interaction between chemically vitiated Doshas and Dushyas. This is called Vikruta vishama Samoorchana. It is the two types of interaction which influences the srotamsi in four ways and this is why 4 types of Srotodushti have been mentioned. But from the point of view of ultimate effect these 4 types of Srotodushti are mainly and primarly concerned with hyperactivity (Atipravritti ) or hypoactivity ( Sanga ) of Srotamsi. If the cardinal symptoms of the disease are related with the Srotodushti they should be functionally hypo or hyper in nature. Onviously Sanga may or may not lead to Vimargagamana and the Siragranthi is to indicate the structural lesion as when occurred. Two states of Srotamsi in a disease condition are mentioned in Ayurvedic classics viz.

Hyper activity or Hypo-activity. Obviously,

therefore, the therapeutic measures would be required to be employed to rectify these conditions. A student of Dravyaguna knows well that sheeta restricts the movements while Ushna accelerates the movement of Srotamsi – Generally speaking the Kapha and vata indirectly contribute to sanga and in most of the cases Pitta contributes to Atipravritti. However, this cannot be a hard and fast rule. But the selection of Sheeta and Ushna with reference to the qualities of Doshas involved indicate the influence of Doshas on srotamsi and its rectification by the Sheeta – Ushna therapies.

Our attention is

naturally drawn to the Swedana and Sthambhana Upakramas and their therapeutic implications which clearly points to the relaxation and constriction of the Srotamsi along with expulsion and retention of the substances therein. Since all these phenomena are very much imperative to be tackled while curing a disease, Acharya Charak, having specific sight and attitude in the field of treatment, preferred to attach more importantance to Basic concepts of Ayurvedic pharmacology114

two qualities namely Sheeta and Ushna. So much so that he preferred to classify Virya into groups on the aforesaid grounds only.

Charaka’s

preference reflects his clinical sense and skill. Let us, therefore, postulate a view here that the jurisdiction of Sheet and Virya is confined mainly to the Srotamsi. It should be clear to us that the things are being talked about at the cellular level here involving osmosis, infiltraction, cellular metabolism – all depending upon the permeability of the cell wall. The retardation or the acceleration of the permeability of the cell wall are in question when Charak ascribed importance to Sheeta and Ushna Virya. However, he does not negativate or contradict the Ashtavidha Viryavada nor Susruta decries the Dwividha Viryavada. It is, therefore, a simple question of preference and attitude rather than conflict or contradiction between Charak and Susruta. Even the Ashtavida Virya vada includes Sheeta – Ushna Viryas and its location and jurisdiction should be accepted as described above. The two types of classifications of Nidanas as Sanarpak and Apatarpak; the two types of results of vitiation as Kshaya and Vriddhi; the two broad groups of Shadwidhopakramas incorporating three Upakrakas in to each; two modes of treatment in general expressed in form of similar and dissimilar ( Samanya – Vishesha); the two types of origination of disease Amasayoth, Pakwasayoth all these probably tempted Maharshi Charak to offer preference to Sheeta and Ushna virya. At this juncture we are also reminded of specific site of action which more or less relates to specific Srotamsi where in the Vyakti stage of samprapti takes place. We are also reminded of the fact that there are Samanyaja and Nanatmaja Vikaras. Symptoms, no doubt, are caused in other stages of Samprapti also. But it is christened as Samanyaja Vikaras only when the Vyakti stage is accomplished and srotodushti symptoms become manifested.

It is at this stage that Virya should prove

YATSADHAYANTI TAT PHALAM i.e. result is the cure disease. Basic concepts of Ayurvedic pharmacology115

VIRYA VIS –A – VIS SAMPRAPTI STAGES In the foregoing pages we have incorporated the Rasapanchak into the Ashtavidha Virya. Simultaneously we have also tried to fix up the site and area or jurisdiction of the Ashta Vidha Virya. It is time now for us to collaborate all the above said ideas with the Samprati Vighatana of diseases. Drugs do certain action to bring about certain effects corresponding to ‘Yat Kurvanti Tat Karma’ and ‘Yat Sadhayanti Tat Phalam’ Obviously, therefore, the therapeutic utility of drug is studied by observing its effect on the disease and its mode of action to achieve that effect. In the rational definition of treatment, the Samprapti Vighatan is given due importance. Any therapy that dismantles the Samprapti at any of its stages is called treatment. In other words cure of disease is nothing but correction of Samprapti. The Samprapti is a chain of events caused by the vitiated Doshas starting from Koshta, and, from there, spreading into different Srotamsi ultimately interacting with a particular Dushya at a particular place to engender a particular disease. The stages of Chaya and Prakopa take place in the Koshta in the respective abodes of the Doshas.

The prasara and Sthahasamsraya stages involve

Srotamsi and the Vyakti stage biochemically relates to Doshadushya Samoorchana wherein the dushyas are mainly involved affecting the Srotamsi and causing sroto-dushti. Thus Koshta, Dushyas and Srotamsi are involved in the pathogensis of the disease. In the preceding pages the relations of Ashtavidha Virya with different sites, viz., Mrudu-Tikshna at the tongue level, Snigdha – Ruksha at Koshta level, Guru - Laghu at Dhatu level, and Sheeta-Ushna at Srotamsi level, was postulated so that the different stages of Samprapti related to different sites such as Koshta, Dhatu and Srotamsi may be dismantled by Snigdha-Ruksha, Guru-Laghu and SheetBasic concepts of Ayurvedic pharmacology116

Ushna Viryas respectively. A very pertinent question can be asked here as to how are we going to determine a particular drug has dismantled the Samprapti by its particular Virya. This question can safely be satisfied by preparing a proforma of Symptoms of the disease in relation to pathogenic stages and the sites involved. Now give a drug and note down as to which of the symptom disappeared first. Find out the relationship of those symptoms with the site and stage of Samprapti and presume that the drug has acted on that particular stage. Now find out the Virya (Out of eight Viryas) of that drug and fix up the relationship of a particular Virya with that stage of Samprapti. Let us painfully admit that we cannot prove rationally of the drug action unless we prove these things on the above presumptions. If we do not start the hypothesis the present practice of haphazard description of rationality drug action would continue to deteriorate the scientificity of Ayurvedic therapeutics.

VIRYA VIS- A- VIS SHADWIDHOPAKRAM One of the prime objects of Ayurvada is to mitigate or cure the disease. Obviously, therefore, the concepts of treatment have been very rationally and scientifically evolved. Despite different types of classification of treatment, the more suitable and comprehensive classification comprises of six therapies called ‘Shadwidhopakram’. The arrangement and division of treatment in to these six therapies encompasses every other classification of treatment. The fundamental principle of treatment is to dislodge the Samprapti, which involves dosha, dushya and srotamsi. The Shadupakramas, therefore should aim at the rectification of the morbidity of either the doshas or dushyas or srotamsi as the case may be. As a matter of principles, therefore, it become imperative for a thinker to locate and understand the Basic concepts of Ayurvedic pharmacology117

relationship between the pathogenic events and these Shadupakramas. Elsewhere in this paper only, it was pointed out and concluded the logical necessity and scientific utility of fixing up of different stages of pathogenesis in relation to the treatment thereof. In order to confirm the previous propositions, the Shadupakramas are selected for correlating with different stages and locations of Samprapti as follows –

Stages of

Location of

Samprapti

stages

Shadupakrama

Virya

i) Chaya

Koshta

i) Snehana

Snigdha Virya

ii) Prakopa

Koshta

ii) Rukshana

Ruksha Virya

iii) Prasara

Dhatu

iii) Brimhana

Guru Virya

iv) Sthanasam

Dhatu

iv) Langhana

Laghu Virya

Srotas

v) Swedana

Ushna Virya

vi) Sthambana

Sheeta Virya.

sraya v) Vyakti

From the above schematic presentation it becomes clear that treatment with drugs should inevitably and invariably involve different Viryas and this involvment should be incoroporated in to the Shadupakramas. With this view only the qualities accepted as Virya by the Ashtavidha Virya Vadis find a predominant role in the Shadupakramas viz; Snehana-Rukshana on account of Snigdha and ruksha virya, SwedanaShambhana on account of Ushna-Sheeta Virya and Langhana-Brimhana on account of Laghu-Guru Virya respectively.

The two Viryas i.e.Mrudu-

Tikshna have not been given much prominence in describing systemic actions of the drug as those two Viryas seem to be concerned with local actions. However, they are mentioned in the substances described to be doing Basic concepts of Ayurvedic pharmacology118

one of the six actions in the body.

Objections could be raised against

fixation of the Shadupa-kramas with respect to their actions in a particular location.

It may be argued that by restricting the jurisdiction of these

Upakramas to the particular sites of the body their local and general application would become irrelevant. This argument will not be altogether wrong as biological variables obviously reflect in the variations of the treatment as well as its application. However, preference to one should not mean the rejection of the other. It is a matter of selection and suitability. When we talk of dosha, dushya and Srotamsi we imply thereby certain minutest substances involved in the causation of the disease and those substances are in one way or the other interrelated and interdependent. This is why the pathogenesis is described as a chain of events rather than a separate entity in itself. So also eventhough the Karmas have been fully ascribed to the drug, its fractions have been divided into Rasa Panchakas and these Rasa Panchakas have been discretely mentioned to be activated at different levels of Samprapti. The relationship of Vipakas with the actions they produce in the gastrointestinal tract has been explained on the basis of Snigdha-ruksha property, which the Ashtavidha Viryavadis called as Snigdha and Ruksha Viryas and which the clinicians call them as Snehana and ruksnna therapies. In the present context Snehana Upakrama implies with Abhyantara Sneha. The Bahya sneha also in one way or the other relates to the subsidence of doshic symptoms or pushing the doshas from the systemic circulation to Koshta where from they can be thrown out of the body by emesis or purgation.

This is why external and internal application of

Snehana is Poorva Karma and does not form the body of the main treatment. Coming to the Srotamsi and their involvement in the pathogenesis, the Acharyas detected and defined the hyper or hypo motility of the Srotamsi Basic concepts of Ayurvedic pharmacology119

implying thereby that osmosis, transaction of the nutrient substances and permeability of the cell wall may decrease or increase. The question of Srotamsi in the patogenesis implies the tiniest structures including the cell wall as the disease is thought of at the cellular level. Such being the case the common observation of the effect of cold and heat on different Srotamsi resulting in their hyper or hypo functioning was probably the clue which the Acharyas clinched to explain Sheeta and Ushna Viryas vis-à-vis Srotamsi. As pointed out earlier the action of drugs on different Srotamsi in the body may be explained on the basis of sheeta and Ushna Virya. This postulation reflects in the clinician’s view of Shadupakrma where in the qualities of Sthambhana upakaram may lead to the constriction of channels while Swedana upakrama may lead to the dilatation of the channels. Out of these qualities ascribed to these upakramas, ushna plays a predominant role in Swedana while Sheeta plays predominent role in sthambhana. This led the Ashtavvidha Virya vadis to pick up these qualities as one of the Viryas. Let us now come to the dhatus which play which play a prominent role in Dosha-Dushya Samoorchana by biophysical and biochemical interactions and thereby causing the symptoms of disease through one of the Srotodushti Lakshanas. A detailed study of patients suffering from different diseases revealed one fact beyond doubt that there is a local increase but general decrease of the Dhatus in disease conditions (Ayu 1968 –Rogavastha me Dhatu ki Sthiti). Accordingly the therapeutic measures to rectify the discordance at the tissue level is either to elevate or bring down the qualitative amount of the Dhatus as the case may be. Ultimately the mass of the human body is composed of the Dhatus and their decrease or increase can be qualitatively termed as Guru and Laghu, and the substances affecting these qualities are accepted as Guru and Laghu Viryas by the Ashtavidha Basic concepts of Ayurvedic pharmacology120

Virya Vadis. Giving it a detailed and multiferous appearance the clinicians chose the name as Laghana and Brimhana Upakramas. Even the concept of Ama, while interfering with the normal transaction of the Poshaka Dhatus to the Poshya Dhatus implies Gourava and reverse implies Laghava.

The

Langhana-Brimhana therapies include substances and practices which may bring about the desired effect of the increase or decrease of the Dhatus. In the foregoing lines it is attempted to correlate the states of Dosha, Dushya and Srotamsi with their sites and location in relation to pathogenic stages and the drugs as well as the therapies to mitigate or rectify them at those particular sites.

DRUG ACTION IN GENERAL VIS-À-VIS ASHTAVIDHA VIRYA Drug acts in the body by virtue of certain qualities in them which are similar or dissimilar to the qualities present in different constituents in the body. In a very generalized form the effects of drugs have been summed up to be excitation (Vriddhi) and depression (Ksahya). These two general effects are brought about on the basis of the principles of similar (Samanya) and dissimilar (Vishesha). But then the defect or the deformity involves the systemic chain of pathogenic events leading on to the localization and manifestation of disease. Obviously, therefore, the pathogenic events should be dismantled at a particular site so as to break the chain and cure the disease. Different sites obviously include different Dushyas and Srotamsi along with their Adhisthan or Adhikaran. The ancient Rishis, therefore, thought of different prominent qualities in a drug by which it may act at particular site or at a particular pathogenic state. Since the pathogenic events do not simply imply the transport of pathogenic Dosha from Koshta to the Basic concepts of Ayurvedic pharmacology121

Dhatus, certain chemical changes and functional disturbances at each stage of Samprapti or pathogenesis were thought of. Secondly Dosha, Dushya and srotamsi involved in the pathogenesis have otherwise definite and distinct function to perform in the body in a close cooperative state. Keeping the quality and action of Dosha, Dushya and srotamsi in relation to pathogenic site, it becomes imperative for the scientists to explain drug action at different states of Samprapti and at different sites with different and defined qualities. If certain actions were to be ascribed to certain qualities they were to be named ‘Virya’ as the scientists were committed to the definition that anything of a drug that acts in the body should be called Virya. In view of this concept, Ashtavidha Virya becomes relevant as it goes to explain actions by Snigdha-Ruksha at the level of Koshta, Sheeta-Ushna at the level of srotamsi and Guru –Laghu at the level of Dhatu. Let us now recall the statement of Charak about how drug acts – Whatever, therefore, substances do, whether by virtue of their nature as substance, or by virtue of both, their substantive and qualitative natures, in any given time, at any given place, having been administered in a given mode, with a given result in view – all that is their action. Whereby they act is the potency. Wherein they act is the time. How they act is the mode, what they achieve is the result (Ch. Su. 26/13). The above statement asserts the importance of the substances as obviously qualities without substances are inconceivable.

In the above

statement two words attract our attention – Dravya Prabhavat and Gunaprabhavat. This implies that certain actions may not be explainable on the basis of qualities of the drugs. This idea corresponds to ‘Isomerism’ which is appropriately christened as Prabhava in Rasapanchaka.

The

Basic concepts of Ayurvedic pharmacology122

remaining Rasa, Vipaka, Guna, Virya are implied by ‘Guna Prabavata’. The statement further adds the consideration of Adhikarana and also the actions and results. It is, therefore, imperative for us to explain the mode of action in relation to the site of action. The mode of action according to us would be to rectify the discordance in the Dosha, Dushya and Srotamsi and these even though present throughout the body have certain prominence and locations. This is one aspect. The another aspect is that the drug acts by virtue of Rasa, Vipaka, Guna and Virya. If the drug acts by Virya (ENA KURVANTI TAT VIRYAM) and if the drug action as per the foregoing statement is done by Guna Prabhava, some of the prominent Gunas should be involved in explaining the actions through Rasa, Vipaka and Virya. And this postulation is true because even the Rasa and Vipaka are said to exert their influences on the tongue or on the Koshta mala and mutra by virtue of qualities they have. This is the main basis on which Ashtavidha Virya Vada stands and this is why, on an overall assessment of the relevant facts and literature, we are tempted to prefer Ashtavidha Virya Vada to explain drug action in Ayurveda. However this does not amount to deny the Dwividha Virya Vada as it is also included in Ashtavada. Being a clinician Maharshi Charak seems to attach more importance to Dwividha Virya Vada. But he himself never condemns the Ashtavidha Virya Vada. When different but unconflicting approaches are made to one problem, a comprehensive approach is preferable and this is what makes us to support Ashtavidha Virya Vada. A comprehensive study of the general and specific principles of drug in Ayurveda reveals one fact beyond doubt that drugs act by Virya which is entertained and interpreted in different ways keeping in view the chemical, biological and therapeutic equivalences including Rasapanchak vis-à-vis the Dwividha and Asthavidha Viryas with special reference to the mode of Basic concepts of Ayurvedic pharmacology123

action, selective affinity and therapeutic utility. At the very outset the Virya has been divided in two groups – chintya Virya incorporating the Rasa, Vipaka, Guna and Virya and the Achitya Virya denoting the Prabhava. The scientific rationality rests with the Rasapanchaka sineque non for drug action finding its final expression in Dwividh or Ashtavidha Virya pari pasu the therapeutic utility envisaged in shadupakrama. There is, inter alia, a relationship between these principal postulates at the chemical and therapeutic levels, their independent identity - not withstanding. The concept of Ashtavidha Virya is a comprehensive, nonetheless, all – inclusive approach to drug action, which purports to dismantle the Samprapti at any particular stage so as to avail of the ultimate desired therapeutic effect. In the preceding pages it is attempted to collaborate and corroborate Raspanchaka with Ashtavidha Virya in relation to Samprarti Vighatana. The preference to Ashavidha Virya depends on its being inclusive of Dwividha Virya. An attempt has been made to define and determine specific place with specific function on the one hand and specific quality, the specific therapeutic utility the other. Thus the whole chain of Samprapti, inevitably and invariably involving the Doshas, the Dushyas and Srotamsi has been located at the level of Koshta (Dosha), Srotas and Dhatu. Each of these three require to be corrected by stimulating or depressing as the case may be and, therefore, six most potent qualities have been picked up to be named as and included in Virya – Snigdha – Ruksha at the level of Koshta, Sheeta – Ushna at the level of Srotas and Guru-Laghu at the level of Dhatus. Moreover to insure drug identification along with its primary qualities and their local actions the Mrudu and Tikshna Gunas have also been accepted as Viryas at the tongue level. Thus Ashtavidha Virya encompasses all the aspects of drug action. The Shadwidhopakramas are but the expression of Ashtavidha Virya in therapeutic parlance. There is no controversy or contention between Basic concepts of Ayurvedic pharmacology124

Ashtavidha and Dwividha ViryaVada, as the former, ipso facto, includes the latter. At length, it is now clear that a multi-farious and synthetic approach, on the applicability of various concepts of drug action was adopted in Ayurveda, showing thereby that these schools are not contradictory but they are rather supplementary to one another.

VIRYAM TU KARMA NISHTAYA – AN ASSESSMENT OF VIRYA Despite tremendous advances in the field of research in drugs with special reference to Indigenous medicinal plants, nothing as yet could be finally said about modus operandi of Indigenous drugs, especially in the light of the latest principles of pharmaco-kinetics. It is explicitly stated that drugs do not act by virtue of their Gunas but in fact they act by virtue of their own Swabhava or Gunas or by both. Drug acts by Rasapanchaka i.e., Rasa, Guna, Virya, Vipaka and Prabhava and these principles are known as Gunas in general sense. According to Charaka certain drugs exercise their action by virtue of their Rasa, some by Guna, Virya, some by Vipaka and others by Prabhava. In case the Rasa, Vipaka, Virya and Prabhava are of equal strength, by nature, the Rasa in superceded by Vipaka, both of them in turn are superceded by Virya and Prabhava superceds all the other principles. These concepts of drug action need to be explored and demonstrated further on scientific lines to interpret the action the action of a particular drug. Rasa, Guna, Virya, Vipaka and Prabhava reside in dravya and exercise their own action. Rasas are six in number namely Madhura, Amla, Lavana, Katu, Tikta and Kashaya. Each Rasa is having certain Gunas and Basic concepts of Ayurvedic pharmacology125

the actions of Rasas on different components of the body like Doshas, Dhatus, Malas and Srotas could be explained through these Gunas.

TABLE –I. Rasas and their Gunas Rasa

Guna

Madhura

Snigdha, Sheeta, Guru

Amla

Snigdha, Ushna,Laghu

Lavana

Snigdha, Ushna, Guru

Katu

Rusha, Ushna, Laghu

Tikta

Ruksha, Sheeta, Laghu

Kashaya

Ruksha, Sheeta, Guru

Kashyapa while describing the order of Rasas to be administered in different diseases according to the involvement of Doshas (as mentioned below), interpreted the action Rasas in terms of Gunas.

TABLE-II. First Vata Pitta Kapha

Second

Third

Lavana

Amla

Madhura

(Ushna, Guru)

(Snigdha, Ushna)

(Guru, Pichila, Snigdha)

Tikta

Madura

Kashaya

(Seetha, Laghu)

(Seetha,Guru, Snigdhu)

(Ruksha, Visada)

Katu

Tikta

Kashaya

(Visada, Laghu)

(Seetha, Laghu)

(Ruksha)

Parinama (transformation) is the main lakshna of Vipaka and the Vipaka of a Dravya is classified on the basis of rasa or Guna such as Mahura Basic concepts of Ayurvedic pharmacology126

Vipaka, Amla Vipaka, Guru and Laghu Viapkaas. As stated by Sushruta, the manifestation, predominantly, of the Gunas of Apya and Parthiva Dravyas, in the cause of their Paka, is described as Madhura in Paka. If on the other hand, the end products of Pachana exhibit Gunas, predominantly of Tejas, Vayu and Akasha then, the Paka is described as Katu. Charaka described the actions of Vipaka on Dosha, Dhatu as stated below.

TABLE-III Vipaka

Guna

Dosha

Sukrala

Mala

Madhura

Guru Snigdha

Kaphakara

Sukrala

Srishtavit-mutratwam

Amla

Laghu

Pittakara

Sukranasaka

Srishtavit-mutratwam

Vatakara

Sukranasanam

Baddavitmutratwam

Snigdha Katu

Ruksha, Laghu

It appears from the above table that actions of Vipaka of a Dravya on Dosha, Dhatu and Malas have been explained in term of Gunas. The term Virya has been described as Shakti or power to perform work of any kind. According to Vagbhata the Status of Virya has been conferred upon eight Gunas, because of their being the Sara (essence) of the twenty Gunas, their effectiveness in the performance of actions and the importance attached to them in the description of qualities of Dravyas as compared to Rasas. The eight Gunas viz., Guru-Laghu, Snigdha-Ruksha, Ushna-Sheeta, Mrudu-Tikshana, can with stand Kayagnipaka and generally are not mutable. According to Sushruta Ushna and Sheeta Viryas/Gunas transcend and supercede the specific actions ascribed to Rasas and act by Virtue of their own inherent powers. He has further observed that like Agni Basic concepts of Ayurvedic pharmacology127

and Shoma of the universe, Viryas are also two. Ushna and Sheeta. Eight Gunas/Viryas are also can be classified in Shoma and Agni group as started below. TABLE-IV Agneya

Shoumya

Ushna

Sheeta

Laghu

Guru

Ruksha

Snigdha

Tiksha

Mrudu

If two drugs having similar Rasa, Vipaka and Virya differ in their action, then the causative principle for such distinctive effect should be explained as Prabhava.

Charaka notes that Danti and Chitraka though

similar in Rasa, Vipaka and Virya the former acts as a purgative while the latter does not does not have such action. But Charaka included Chitraka in Bhedaneeya Dasaimani appears to be self-contradictory.

Some scholars

expressed that two different types of Chitraka are intended in two different contexts. But Chitraka Dwaya was not identified at the time of Charaka and both sweta and Rakta Chitraka are possessing similar activity. The Lakshana of Prabhava as explained by Charaka and Vagbhata appears to be imprecise since the similarity of Rasa, Vipaka, Virya does not imply in the case of Manidharana, Vasikaranam, Vishahartwan due to agada darshana etc. Acharya Priyavrat Sarma has interpreted Prabhavajanya Karma from modern science point of view in his book Dravyaguna (Vol. I) as follows :

1 Oushadiya Karma (Pharmacological action): Danti’s purgative action. Basic concepts of Ayurvedic pharmacology128

2 Agadiya Karma (Toxicological action): Anti-toxic property of Shirisha. 3 Rakshoghna Karma (Bacteriological action): Anti-bacterial action of Guggulu, Jatamamsi etc., 4 Manasa Karma (Psychological action): Vasikaranam 5 Bhoutika Karma (Physical action) : Extaction of Shalya (foreign body) with help of a magnet. Above classification appears to be improper because Anti-toxic property of Shirisha has been interpreted as toxicological action. The Rakshoghnakarma (Bacteriological action) comes under one of the Oushadhiya Karma (Pharmacological) actions such as bactericidal or Bacteriostatic actions. Extaction of foreign body (Metallic in nature) by magnet can be explained with the already proved principle of magnetism of modern physics and hence it can not be considered as Achintya Karma. Drugs manifest their Prabhavajanya Karma only so long as not over powered by any other extraneous forces.

Danti when soaked in water does not

manifest purgative action. Virya of a drug can be changed from Guru to Laghu and similarly Prabhavaja Karma of a Dravya can also be modified. It is very difficult to render explanation about modus operandi of compound preparations consisting 40-50 drugs. Rasa of a Dravya can be ascertained immediately after their contact with tongue and the Vipaka by Nishta Karma (final actions).

The Virya can be determined while in

association with the body and also immediately after coming in contact with Basic concepts of Ayurvedic pharmacology129

body. Thus in epistemological terms the Rasa is known by direct perception and Vipaka can by only be inferred from its actions. Virya may some times be inferred from its action and also known by direct perception. The action of Virya or Vipaka of administered drugs should be assessed in term of Doshas, Dhatus and Malas such as Vriddhi or Kshaya, Sukranasa or Sukra Vriddhi and Srushta Vitumutrata or Badda Vitmutratas. It is explicit from the foregoing tables that Rasa and Vipaka of a drug are having certain Gunas and the actions of those principles are explained with the help of the Gunas only. Some potent Gunas have been christened as Virya. The Vipaka can not be consided as one of the principles of drug action, since it is a process of transformation (Parinama) where in the Gunas are undergoing changes. So any action during such process will be attributed to Gunas that are undergoing Paka. The two attributes viz., Virya and Prabhava should be considered for imparting rationality to the Ayurvedic concepts of drug actions instead of five principles. Virya of a Dravya should be assessed by Vishta Karma. Assessment of Gurvadigunas at biological level is very important. Important Sushruta has given assessment of certain Gunas as follows :-

TABLE-V Gunas

Perception

Mrudu-Sheeta-Ushna

Sparsha.

Visada Pichila

Sparsha & Chakshusha.

Snigdha-Ruksha-Tikshana

Mukhadukhotpadana.

From above description it appears that the assessment/identification of Guna is made by Organo-leptic methods. Sushruta also quoted certain Karmas for Viryas and are as follows :

Basic concepts of Ayurvedic pharmacology130

TABLE-VI Virya

Dosha

Other Karmas

1. Sheeta

Pittahara

Jivaneeya, Prasadana, Sthirikarana.

2. Ushna

Vatahara

Pachana, Swedana, Dahana, Vamana.

3. Snigdha

Vatahara

Snehana, Brihmana, Vajikaran, Vayasthapana.

4.Ruksha

Sleshmahara

Sangrahana, Rukshana, Ropana, Pidana.

5. Guru

Vatahara

Upalepa, Brimhana.

6. Laghu

Sleshmahara

Lekhana

7. Mrudu

Pittahara

Raktamamsprasadana.

8. Tikshna

Sleshmahara

Sravana, Sangrahana.

Shadupakramas i.e., Laghana, Brimhana, Snehana, Rukshana, Swedana, and Sthambhana are performed by drugs consisting of Gunas like Laghu, Guru etc. Hemadri has attempted to enumerate specific actions of different Gunas at biological level as follows : 1. Guru

-

Which does Brimhana Karma

2. Laghu

-

Which does Langhana Karma

3. Sheeta

-

Which does Sthambhana Karma

4. Ushna

-

Which does Sveda Karma

5. Snigdha

-

Which does Kledana Karma

6. Ruksha

-

Which does Rukshana Karma

7. Mrudu

-

Which does Sthambhana Karma

8. Tikshana

-

Which does Sodhana Karma

Certain Parameters should be evolved for the identification and assessment of these Gunas of a Dravya at the biological level for rational interpretation of Ayurvedic principles of drug action. Basic concepts of Ayurvedic pharmacology131

4. EXPERIMENTAL STUDIES The better understanding of mechanism of drug action will lead to its proper application in diseases.

Ayurveda delineated five principles viz;

Rasa, Guna, Virya, Vipaka and Prabhava which play a definite role for the elucidation of any drug action. A given drug exercises its action at certain sites in the body. Charaka has explicitly stated that “Yatra Kurvanti tat Adhikaranam” where the drug acts is Adhikaranam (site). Doshas, Dhatus, Malas and Srotamsi form the Adhikaranam for any drug to act in the body. As the Virya plays a pivotal role round which whole phenomena of drug action rotates, it is imperative to establish a relationship between different Viryas vis-à-vis various Adhimaranams. As proposed earlier, Ashta Viryas, are correlated with certain sites in the body with respect to their actions. With a view to substantiate correlations in a practical way the following experiments have been carried out:1. Experiments on Isolated frog Heart. 2. Experiments on Frog skeletal muscles. 3. Studies of B.M.R in healthy volunteers.

Experiments on Isolated Frog Heart It has believed as mentioned in the propositions earlier that the sphere of activity of Sheeta and Ushna Virya is at the Srotamsi level. Therefore, it was decided to plan some experimental model on objective basis so as to evaluate the sphere of activity of these two Viryas. The term Srotamsi in general comprehends all channels big and small, perceptible and imperceptible – that comprise the internal transport system, of the body. Some scientists have compared the Srotamsi to capillaries and this Basic concepts of Ayurvedic pharmacology132

interpretation is conductive to consider the heart as the seat of Srotamsi. It is observed in the experimental physiology that variations of temperature alter the heart rate –cold perfusion fluid slows down the heart rate and may finally stop it, while with warm perfusion fluid the heart rate increases. It could therefore, be assumed that Ushna Virya drugs may augment the heart tate where as Sheeta Virrya drugs may decrease it. Keeping these observations in view a study has been carried out to assess the defect of 16 Ushna and 16 Sheeta virya drugs as listed in the following table following on Isolated frog heart muscle.

EFFECT OF USHNA AND SHEETA VIRYA DRUGS ON FROG HEART

Basic concepts of Ayurvedic pharmacology133

Basic concepts of Ayurvedic pharmacology134

Table-2 S.No.

Ushna Virya Drugs

Sheeta Virya Drugs

1.

Apamarga

Anantamoola(Sariba)

2.

Ativisha

Ashoka

3.

Bakuchi

Atibala

4.

Chitraka

Bhavya

5.

Gambhari

Brahmi

6.

Haridra

Gokshura

7.

Jatiphala

Jivanti

8.

Kalamegha

Kanchanara

9.

Manjista

Kutaj

10.

Nagakeshar

Lodhra

11.

Parijata

Musta

12.

Pushkaramoola

Raktachandan

Basic concepts of Ayurvedic pharmacology135

13.

Pippali Moola

Satavari

14.

Talispatra

Ushira

15.

Varahikanda

Vasa

16.

Vidanga

Yastimadhu

Methods and Materials: Drugs for the present study are selected at random. In the present experiments the aqueous extracts of sixteen Ushna and sixteen Sheeta Virya drugs were used.

Preparation of Aqueous extracts: The aqueous extract of the experimental drugs was prepared by taking 10 gm of powdered material immersed in 100 ml distilled water with intermittent shaking and kept for 24 hours and then filtered.

The

filtration was carried out through whatman filter paper No.1 and at least two washes with distilled water were given. The volume was then made up to 100 ml by adding further quantity of distilled water.

Howell has mentioned in his text book of physiology that “The heart is rather remarkably resistant to changes in the acid base composition of its perfusate, and beats have been reported to persist with perfusates as acid as pH 5.5 and as alkaline as pH 10.” However, the pH values of the 10 percent aqueous extracts used in our experiments recorded by a digital pH meter and are given below.

Basic concepts of Ayurvedic pharmacology136

Table-3 pH Values of Ushna Virya

pH Values of Sheeta

Drugs

Virya Drug

Gambhari

5.88

Ashoka

4.95

Vidanga

4.83

Anantamoola

4.73

Bakuchi

6.37

Kanchanar

4.84

Manjista

5.00

Vasa

7.34

Pippalimoola

5.34

Brahmi

5.66

Citraka

5.22

Ushira

5.36

Varahikanda

5.85

Musta

5.59

Jatiphala

5.05

Satavari

5.20

Apamarga

6.45

Yastimadhu

5.65

Nagakesar

4.95

Lodhra

4.52

Kalamegha

7.94

Bhavya

5.17

Pushkaramoola

4.71

Gokshura

5.69

Ativisha

5.22

Jivanti

5.41

Parijata

6.10

Kutaja

5.23

Haridra

6.05

Atibala

6.10

Talisaptra

4.70

Raktachandan

5.89

Preparation of the experiment Model: Conventional method was followed as suggested by Burn (1954) for this experiment.

Apparatus: Needle, Forceps, Scissors, Syringes (Hyprodermic), perfusion apparatus with Sym’s cannula, Starlings heart lever etc.

Basic concepts of Ayurvedic pharmacology137

Perfusion fluid was prepared as per the following formula: 1. Sodium Chloride (Nacl)

9.0 g

2. Potassium Chloride (Kcl)

0.42 g

3. Calcium Chloride (Ca Cl2)

0.24 g

4. Sodium bi-carbonate (NaH Co3)

0.5 g

5. Dextrose (Glucose)

1.0 g

Dissolved in 1.4 liters of distilled water. pH of the Ringer’s solution was 7.5. Total 32 health frogs were used to screen the effect of Ushna and Sheeta Virya drugs. Frog was Pithed and heart was exposed by removing skin and the sternum. The pericardium was removed and the liver was separated from the inferior vena cava as far as the hepatic veins. The right aorta was tied and loose ligature was placed under the inferior vena cava. The heart was held in the forward position by a swab of moist cotton wool. The perfusion fluid was kept ready and a cut was given in the vena cava at the level of hepatic veins and Sym’s cannula was inserted and tied in that position. Mean while the left aorta was given a cut for drainage of the perfusion fluid from the heart. The heart was isolated by separating the surrounding tissues very gently. Perfusion was kept at a constant level in the cannula and constant temperature of perfusion fluid was also maintained. Normal tracing of heart rate was recorded on the smoked drum for 5 minutes and the aqueous extracts in different doses were administered and the effect on the heart was recorded on the smoked paper itself.

Result The effect of Ushna and Sheeta Virya drugs in different doses was Basic concepts of Ayurvedic pharmacology138

assessed on the basis of heart rate and force of contraction (Amplitude) of isolated frog heart during and after perfusion. Individual drug assessment in terms of chronotropic activity that is effect on heart rate and Inotropic activity that is effect on amplitude is stated below.

Ushna Virya Drugs 1. Talisapatra –In 0.2ml, 0.4ml and 0.6ml doses negative inotropic activity was observed which is in ascending order of dose level. No chronotropic activity was seen. 2. Parijata- Negative inotropic activity was observed in 0.2 ml, and 0.4 ml and 0.6 ml doses. The effect was almost same in all the dose. No chronotropic activity was observed at the dose levels.

No

chronotropic activity was observed with 0.6 ml and 0.8ml doses. 3. Varahikanda – Negative inotropic activity was noted at the dose level of 0.2 ml, 0.4 ml, 0.6 ml and 0.8ml at the dose level of 0.2 ml, and 0.4 ml but negative chronotropic activity was observed with 0.6 ml 0.8 ml doses. 4. Gambhari – Negative inotropic activity was observed at the dose level of 0.2 ml, 0.4 ml and 0.6 ml. The effect was in ascending order of the dose levels. No chronotropic activity was observed at any dose level. 5. Pushkaramoola – Negative inotropic activity was observed at the dose level of 0.2 ml, 0.4 ml and 0.6 ml and the effect was in ascending order of different doses. No chronotropic activity was observed at any of these dose levels. 6. Nagakeshara – Negative chronotropic activity was observed at the dose of 0.2 ml and negative inotropic activity was observed at the Basic concepts of Ayurvedic pharmacology139

dose level of 0.4 ml. 7. Chitrak – Positive inotropic activity was seen at the dose level of 0.2 ml, 0.4 ml, and 0.6 ml and the effect was observed to be similar in all doses. Positive chronotropic activity was observed at the dose of 0.2 ml only. 8. Bakuchi – Negative inotropic activity was observed at 0.2 ml, 0.4 ml and 0.6 ml dose level and the effect was in ascending order of dose levels. Negative chronotropic activity was observed with 0.2 ml and 0.4 ml doses. 9. Pippalimoola – Negative inotropic activity was seen with the dose of 0.2 ml and 0.4 ml and the effect was observed to be similar at all dose levels. Negative chronotropic activity was observed with 0.4 ml dose. 10. Manjishta – No inotropic activity was noticed with 0.2 ml, 0.4 ml and 0.6 ml doses. Positive chronotropic activity was observed with 0.2 ml dose and negative chronotropic activity with 0.4 ml. 11. Kalamegha – Negative inotropic activity was observed with 0.2 ml and 0.4 ml doses and the effect was in ascending order of dose levels. No chronotropic activity was seen at 0.2 ml and 0.4 ml and 0.6 ml dose levels. 12. Apamarge – Negative inotropic activity was seen with doses of 0.2 ml and 0.4ml and the effect was in ascending order of dose levels. Negative chronotropic activity in ascending order of dose level was observed with 0.2 ml and 0.4 ml doses. 13. Haridra – Negative inotropic activity was observed with 0.2 ml, 0.4 ml and 0.6 ml dose levels and the effect was found to be in ascending Basic concepts of Ayurvedic pharmacology140

order of dose levels. 14. Jatiphala – Negative inotropic activity was observed with 0.2 ml and 0.4 ml doses and the effect was in ascending order of dose levels. No chronotropic activity was observed at both these dose levels. 15. Vidanga – Negative inotropic activity was observed with 0.2 ml and 0.4 ml doses and the effect was in the ascending order of dose levels. Negative chronotropic activity was seen with 0.2 ml dose only. 16. Ativisha – Negative inotropic activity was noticed with 0.2 ml, 0.4 ml and 0.6 ml doses and the effect was found to be similar at all dose levels. Positive chronotropic activity was observed with 0.2 ml, 0.4 ml and 0.6 ml doses and similar effect was obtained. Sheeta Virya Drugs 1. Vasa – Negative inotropic activity was seen at the dose level of 0.2 ml, 0.4 ml and 0.6 ml and the effect was similar.

Positive

chronotropic activity was observed with the dose of 0.2 ml and negative chronotropic activity was noted with the dose of 0.4 ml. But slight positive chronotropic activity was observed with 0.6 ml dose. 2. Ushir – Negative inotropic activity was observed with 0.4 ml dose and no chrotropic activity was noticed at 0.2 ml and 0.4 ml dose levels. 3. Kanchanara – Negative inotropic activity was seen at the dose of 0.2 ml, 0.4 ml and 0.6 ml and the effect was in ascending order of dose levels. No chronotropic activity was observed with 0.2 ml, 0.4 ml and 0.6 ml doses. 4. Kutaja – Negative inotropic activity was observed with 0.2 ml and 0.4 ml dose but no chronotropic activity was observed at these dose Basic concepts of Ayurvedic pharmacology141

levels. 6. Gokshura – Complete heart block occurred with the dose of 0.2 ml, 0.6 ml and 0.8ml. The effect was in ascending order of dose levels. Negative chronotropic activity was observed with 0.2 ml, 0.6 ml and 0.8 ml doses. 5. Bhavya – Negative chronotropic activity was observed with 0.2 ml, 0.4 ml and 0.6 ml doses. Positive inotropic activity was seen at 0.2 ml dose while negative inotropic activity was observed with 0.4 ml dose. 6. Stavari – Positive inotropic activity was observed with 0.2 ml and 0.4 ml dose and no chronotropic activity was seen with these doses. 7. Ashoka – positive inotropic activity was observed with 0.2 ml and 0.6 ml doses and negative chronotropic activity was observed with 0.2 ml dose. 8. Anantamoola – Negative inotropic and chronotropic activity was observed with 0.4 ml dose only. 9. Rakta Chandan – Negative inotropic activity was observed with 0.2ml and 0.4 ml dose and complete block occurred at the 0.6 ml dose. Positive chronotropic activity was seen with 0.2ml and 0.4 ml whereas at 0.6 ml dose level negative chronotropic activity was observed. 10. Brahmi – Negative chronotropic activity was observed at 0.2 ml, 0.6 ml and 0.8 ml dose levels but no inotropic activity was seen with these doses. No change was observed with 0.4 ml dose either in amplitude or heart rate. 11. Lodhra – Negative Inotropic and chronotropic activity was observed Basic concepts of Ayurvedic pharmacology142

with 0.4 ml dose while positive chronotropic activity was noticed with 0.2 ml dose. 12. Yastimadhu – Negative chronotropic activity was observed with 0.2 ml and 0.4 ml doses and negative inotropic activity was seen with 0.2 ml dose only. 13. Jatamansi – No inotropic or chronotropic activity was noticed at 0.2 ml, 0.4 ml and 0.6 ml dose levels. 14. Atibala – Positive chronotropic activity was observed at the 0.2 ml dose level and no effect was observed on amplitude or heart rate at this dose level. 15. Musta – Negative chronotropic activity was observed with the doses of 0.2 ml, 0.4 ml and 0.6 ml and the response was not corresponding to different dose levels. Negative inotropic activity was seen at 0.4 ml dose only. The number of drugs which have shown positive as well as negative inotropic and chronotropic activity are given bellow in tables 7 and 8 respectively. Table 7: Showing the number of drugs of positive and negative Inotropic activity.

Virya

Positive 0.2 ml

Ino. 0.4

Negative 0.2 ml

ml Sheeta Ushna

6 2

Ino. 0.4 ml

1 1

8 13

11 14

Table 8: Showing the Number of drugs of positive and Negative

Basic concepts of Ayurvedic pharmacology143

Chronotropic activity.

V irya S

Po sitive 0.2 ml 4

C hro 0.4 ml

Ne gative 0.2 ml 7

1

heeta

C hro 0 .4 ml 1 0

U

3

2

8

7

shna The effect of Ushna and Sheeta Virya drugs on amplitude and heart rate was statistically analysed by applying paired “t” test and the results are given bellow. Table 9: Showing the statistical analysis of the effect of Sheeta and Ushna Virya drugs on the amplitude of frog heart. Valu es

Shee ta

Vir ya

0.2 Mean Diff SD SE “t” “p”

ml -0.21 ±0.7 2 ±0.1 8 1.16 0.05

Ush na

0.4 ml

ya 0.2

ml 0.22 ±0. 32 ±0. 08 2.75 0.05 £

Vir 0.4 ml

0.28 ±0.3 6 ±0.9 3.1 0.1£

0.45 ±1. 42 ±0. 35 3.75 0.01 £

£=significant. Table 10: Showing statistical analysis of the effect of Sheeta and Ushna Virya drugs on the heart rate of the frog.

Basic concepts of Ayurvedic pharmacology144

Val ues

0.2 ml Me an Diff. SD SE “t” “p”

hna

ya

eta

Us

Vir

She

0.0 5£

7.25 ±1 5.32 ±2. 83 1.8 9 0.05£

rya 0.4

0.2

0.4 ml

6.3 ±19 .3 ±4. 83 1.3

Vi

ml 0.25 ±5. 6 ±1. 4 0.1 7 0.0 5£

ml 2.06 ±7 .88 ±1 .97 1.0 4 0.0 5£

£ = Insignificant. The amplification was significantly decreased with Sheeta Virya drugs at the dose of 0.4 ml only while Ushna Virya group decrease of Heart rate with both the Sheeta and Ushna Virya drugs at 0.2 ml and 0.4 ml doses was observed. It is evident from table 7 and 8 that both Sheeta and Ushna drugs have exhibited positive as well as negative inotropic and chronotropic activities.

However, large number of drugs have shown positive

chronotropic activity from Sheeta Virya group at 0.2 ml dose as compared to Ushna Virya drugs exhibited negative inotropic activity at the dose level of 0.2 ml and 0.4 ml as compared to Sheeta Virya drugs have decreased the heart rate (Negative chronotropic activity) at the doses level of 0.2 ml and 0.4 ml than those in Ushna Virya group. Since it was not possible to screen all the drugs at different dose levels the statistical analysis was given to the doses of 0.2 ml and 0.4 ml at which all the experimental drugs were screened. It has been shown in the table that both Sheeta and Ushna Virya drugs have exhibited depressant action on the amplitude (Negative Inotropic). Sheeta Virya group has shown significant decrease of amplitude Basic concepts of Ayurvedic pharmacology145

(P