Pharmacology

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Pharmacology Questions PHARMACODYNAMICS 1.

Competitive inhibitors ________ (do/do not) resemble the substrate, while noncompetitive inhibitors ________ (do/do not) resemble the substrate. (p. 232)

2.

The value of Km reflects the _______________ of the enzyme for its substrate. (p. 232)

3.

True or False: In enzyme kinetics, the lower the Km, the higher the affinity. (p. 232) _____________  232) _____________ 

4.

Vmax is directly proportional to the _______________ _______________. (p. 232)

5.

A graph of substrate concentration on the x-axis and velocity of the reaction on the y-axis has has  _______________ (increasing/decreasing) velocity as substrate is increased, although it will plateau when the enzyme is saturated. (p. 232)

6.

When velocity is equal to one half of its maximum (Vmax), the corresponding concentration of substrate is equal to what value? (p. 232) _____________________________________________ 232) _____________________________________________

7.

Use the graph below to answer the following questions. (p. 232)

8.

 A.

What pharmacodynamic term describes the x-intercept of the line? _____________________

B.

What pharmacodynamic term describes the y-intercept? ____________________________

C.

If the y-intercept increases, how is the maximum reaction rate affected? _________________

D.

If the x-intercept moves to the right (increases), how how is the Km affected? _________________

In enzyme kinetics, a competitive inhibitor ________ (can/cannot) be overcome by increasing the concentration of substrate; a noncompetitive inhibitor ________ (can/cannot) be overcome by increasing the concentration of substrate. (p. 232)

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9.

Competitive inhibitors _______________ (increase/decrease/do not change) the Vmax  of the reaction, whereas noncompetitive inhibitors _______________ (increase/decrease/do not change) the Vmax of the reaction. (p. 232)

10.

Competitive inhibitors _______________ (increase/decrease/do not change) the Km  of the reaction, whereas noncompetitive inhibitors _______________ (increase/decrease/do not change) the Km of the reaction. (p. 232)

11.

What is the formula for calculating a drug’s volume of distribution? (p. 232) ___________________ 232) ___________________

12.

Drugs with a low volume of distribution are found in the _______________ (blood/tissue/extracellular space). Drugs with a high volume of distribution are most likely found in the _______________ (blood/tissue/extracellular space). (p. 232 )

13.

What is the formula for calculating a

14.

What is the definition of the half-life of a drug? (p. 232) ___________________________________ 232) ___________________________________

15.

For a drug that is infused at a constant rate, how many half-lives must pass before the drug reaches approximately 94% of steady-state concentration? (p. 232) ________________________ 232) ________________________

16.

Given the volume of distribution and clearance of a drug, how is the drug’s half -life -life calculated? (p. 232) __________________________________________________________________________ 232) __________________________________________________________________________

17.

After one half-life, given constant intravenous infusion of a drug, how close to steady state is the -lives? (p. 232) _________________________ 232) _________________________ drug’s concentration? How close is it after three half -lives?

18.

What is the formula for calculating a drug’s loading dose? (p. 233) __________________________ 233) __________________________

19.

What is the formula for calculating the maintenance dose dose of a drug administered intravenously? (p. 233) __________________________________________________________________________ 233) __________________________________________________________________________

20.

How do the loading and maintenance doses of drugs differ for patients patients with renal or liver disease? (p. 233) ________________________________________________________________________ 233) ________________________________________________________________________

21.

What is the bioavailability (%) of a drug if it is administered intravenously? (p. 233) _____________ 233) _____________

22.

In zero-order elimination of drugs from the body, what is the relationship between the rate of elimination and the drug concentration? (p. 233) ________________________________________ 233) ________________________________________

23.

Name three drugs that exhibit zero-order elimination. (p. 233) _____________________________ 233) _____________________________

24.

In first-order drug elimination, what is the relationship between the rate of elimination elimination and the drug concentration? (p. 233) ___________________________________________________________ 233) ___________________________________________________________

25.

A 24-year-old 24-year-old man attempts suicide by consuming consuming the contents of a small bottle bottle of aspirin. Three hours later he is brought to the emergency room, where he is administered intravenous saline with bicarbonate. By what mechanism does this help him? (p. 233) 233) _____________________________

drug’s clearance? (p. 232) ____________________________ 232) ____________________________

 ______________________________________________________________________________ 26.

A drug that requires a very low dose to achieve achieve its desired effect is _______________ (effective/potent). (p. 233)

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27.

The graph below shows the effects of two types of antagonists on an agonist. What type of antagonist is represented by curve A? By curve B? (p. 234) _______________________________ 234) _______________________________

28.

The addition of a noncompetitive agonist agonist _______________ _______________ (increases/decreases/does not change) the efficacy of the agonist. (p. 234)

29.

How does the efficacy of a partial agonist relate to the efficacy of a full agonist of the same receptor? (p. 234) ________________________________________________________________ 234) ________________________________________________________________

30.

How does the potency of a partial agonist relate to the potency of of a full agonist of the same receptor? (p. 234) ________________________________________________________________ 234) ________________________________________________________________

AUTONOMIC DRUGS 31.

How does botulinum toxin work? (p. 235) _____________________________________________ 235) _____________________________________________

32.

Identify the G-protein class for each each receptor. (Numbers may be used more than once.) (p. 236)  _____ A. α1  _____ B. α2  _____ C. β1  _____ D. β2  _____ E. D 1  _____ F. D2  _____ G. H1  _____ H. H2  _____ I. M1  _____ J. M2  _____ K. M 3  _____ L. V1  _____ M. V2

33.

1. 2. 3.

Gi Gq Gs

What are the major effects of α 1-receptor activation? (p. 236) ______________________________ 236) ______________________________  ______________________________________________________________________________

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34.

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What are the major functions of α 2-receptor activation? (p. 236) ___________________________ 236) ___________________________  ______________________________________________________________________________

35.

What are the major functions of β 1-receptor activation? (p. 236) ____________________________ 236) ____________________________  ______________________________________________________________________________

36.

What is the major effect of β 2-receptor activation on the body's vasculature? What is the effect on the respiratory system? (p. 236) _____________________________________________________ 236) _____________________________________________________

37.

How

38.

In the images below, identify which autonomic drugs work at which site of action. (p. 237)

236) __________________________ does β2-receptor activation affect glucagon release? (p. 236) __________________________

(Adapted, with permission, from Katzung BG, Trevor AJ. Pharmacology: Pharmacology: Examination & th Board Review, Review, 5   ed. Stamford, CT: Appleton & Lange, 1998: 42.)

39.

Name five indirect cholinergic agonists. (p. 238 ) ________________________________________  ______________________________________________________________________________

40.

What symptoms are likely in patients taking cholinomimetic agents? (p. 238) __________________ 238) __________________  ______________________________________________________________________________

41.

Which pharmacologic agent is used to treat atropine overdose? (p. 238) _____________________ 238) _____________________

42.

What is a methacholine challenge test? (p. 238) ________________________________________ 238) ________________________________________  ______________________________________________________________________________

43.

A farmer presents with diarrhea, abdominal pain, wheezing, pinpoint pupils, copious tears, and salivation. What medications should be prescribed? (p. 238) ______________________________ 238) ______________________________

44.

Why is pyridostigmine used to treat myasthenia gravis? (p. 238) ___________________________ 238) ___________________________  ______________________________________________________________________________

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45.

A patient recently began taking haloperidol to treat schizophrenia, but visits visits his his physician because of new-onset Parkinson's-like motor symptoms. What drug could be used to treat these symptoms? (p. 239) 239) ________________________________________________________________________

46.

What are the two effects of atropine on the eye? (p. 239) _________________________________ 239) _________________________________

47.

True or False: Diarrhea is a sign of atropine toxicity. (p. 239) ______________________________ 239) ______________________________

48.

 ___ (α1, α2, β1, β2) adrenergic receptors. (p. 240) Low doses of epinephrine are selective for ____ 

49.

Isoproterenol is an agonist for which receptors? (p. 240) _________________________________ 240) _________________________________

50.

Dopamine __________ (is/is not) ionotropic and __________ (is/is not) chronotropic, whereas dobutamine __________ (is/is not) ionotropic and __________ (is/is not) chronotropic. (p. 240)

51.

What are the clinical applications of epinephrine? (p. 240) ________________________________ 240) ________________________________  ______________________________________________________________________________

52.

What role does dopamine have in treating shock? (p. 240) ________________________________ 240) ________________________________  ______________________________________________________________________________

53.

What are the clinical applications of phenylephrine? (p. 240) ______________________________ 240) ______________________________  ______________________________________________________________________________

54.

What is the clinical application for albuterol? (p. albuterol? (p. 240) ____________________________________ 240) ____________________________________  ______________________________________________________________________________

55.

Which sympathomimetics can reduce premature uterine contractions? (p. 240) _______________ 240) _______________

56.

What effect does isoproterenol have on pulse pressure and heart rate? (p. 240) _______________ 240) _______________  ______________________________________________________________________________

57.

What is the effect of clonidine on central adrenergic outflow? On which receptor does it act? (p. 241) __________________________________________________________________________ 241) __________________________________________________________________________

58.

What is the clinical application and mechanism of action of phentolamine? (p. 241) _____________ 241) _____________  ______________________________________________________________________________

59.

What is the net effect of epinephrine on blood pressure before and after nonselective α -blockade? Why? (p. 241) ___________________________________________________________________ 241) ___________________________________________________________________  ______________________________________________________________________________

60.

A 63-year-old man is referred long-term care after his first myocardial infarction. Is a β -blocker suggested or contraindicated for this patient? Why? (p. 242) ______________________________ 242) ______________________________  ______________________________________________________________________________

61.

How do β-blockers work in the setting of angina pectoris? (p. 242) __________________________ 242) __________________________  ______________________________________________________________________________

62.

Which β-blockers have partial agonist activity? (p. 242) __________________________________ 242) __________________________________

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63.

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Name two nonselective α-

and β-antagonists. (p. 242) ___________________________________ 242) ___________________________________

TOXICITIES AND SIDE EFFECTS 64.

Match the specific antidote(s) with each of the toxicities. (p. 243)  _____ A.  _____ B.  _____ C.

Acetaminophen Amphetamines Antimuscarinics and anticholinergics  _____ D. Benzodiazepines  _____ E. β-Blockers  _____ F. Carbon monoxide  _____ G. Copper, arsenic, gold  _____ H. Cyanide  _____ I. Digitalis  _____ J. Heparin  _____ K. Iron  _____ L. Lead  _____ M. Mercury, arsenic, gold  _____ N. Methanol, antifreeze  _____ O. Methemoglobin  _____ P. Opioids  _____ Q. Organophosphates, anticholinesterase inhibitors  _____ R. Salicylates  _____ S. TCAs  _____ T. Theophylline  _____ U. tPA, streptokinase  _____ V. Warfarin 65.

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21.

100% oxygen, hyperbaric oxygen Aminocaproic acid Atropine, pralidoxime β-Blocker CaEDTA, dimercaprol, succimer, penicillamine Deferoxamine Dimercaprol, succimer Ethanol, dialysis, fomepizole Flumazenil Glucagon Methylene blue, vitamin C N -Acetylcysteine -Acetylcysteine NaHCO3 NaCHO3, dialysis NH4Cl Nalaxone/naltrexone Nitrite, hydroxocobalamin, thiosulf ate Phosphostigmine salicylate Penicillamine Protamine + Stop the drug, normalize K , lidocaine, anti-dig 2+ Fab fragments, Mg 22. Vitamin K, fresh fr ozen plasma

Which medications can cause agranulocytosis? (pp. 244-245) _____________________________  244-245) _____________________________   ______________________________________________________________________________

66.

OCPs can cause what kind of complications? (pp. 244-245) _______________________________ 244-245) _______________________________

67.

Which medications can cause hemolysis in patients with G6PD deficiency? (pp. 244-245) _______ 244-245) _______  ______________________________________________________________________________

68.

Which medications can cause gynecomastia? (pp. 244-245) ______________________________ 244-245) ______________________________  ______________________________________________________________________________

60.

Which medications can cause pulmonary fibrosis? (pp. 244-245) ___________________________ 244-245) ___________________________  ______________________________________________________________________________

70.

Which medications can cause photosensitivity? (pp. 244-245) _____________________________ 244-245) _____________________________  ______________________________________________________________________________

71.

Which medications can cause megaloblastic anemia? (pp. anemia? (pp. 244-245) ________________________ 244-245) ________________________  ______________________________________________________________________________ Copyright © 2011 by MedIQ Learning, LLC

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72.

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Which medications can induce seizures? (pp. 244-245) __________________________________ 244-245) __________________________________  ______________________________________________________________________________

73.

Which medications can cause a Parkinson-like syndrome? (pp. 244-245) ____________________ 244-245) ____________________  ______________________________________________________________________________

74.

Which medications can cause a disulfiram- like reaction? (pp. 244-245) ______________________ 244-245) ______________________  ______________________________________________________________________________

75.

Which medications can cause nephrotoxicity and ototoxicity? (pp. 244-245) __________________ 244-245) __________________  ______________________________________________________________________________

76.

In the chart below, checkmark which of the substances are P-450 inducers vs. inhibitors. (p. 245) Substance

P-450 inducer

P-450 Inhibitor

 Alcohol use, acute  Alcohol use, chronic Barbiturates Carbamazepine Cimetidine Erythromycin Grapefruit juice Griseofulvin HIV protease inhibitors Isoniazid Ketoconazole Phenytoin Quinidine Rifampin

St. John’s wort Sulfonamides

77.

How does disulfiram work to treat alcoholism? (p. 246) __________________________________ 246) __________________________________  ______________________________________________________________________________

78.

Which drugs must be avoided in patients with sulfa allergy? (p. 246) ________________________ 246) ________________________  ______________________________________________________________________________

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MISCELLANEOUS 79.

Match the drug name suffix with its category or usage. (Numbers may be used more than once) (p. 247)  _____ A.  _____ B.  _____ C.  _____ D.  _____ E.  _____ F.  _____ G.  _____ H.  _____ I.  _____ J.  _____ K.  _____ L.  _____ M.  _____ N.  _____ O.  _____ P.  _____ Q.  _____ R.  _____ S.  _____ T.  _____ U.  _____ V.  _____ W.  _____ X.

-afil -ane -azepam -azine -azole -barbital -caine -cillin -cycline -etine -ipramine -navir -olol -operidol -oxin -phylline -pril -terol -tidine -triptan -triptyline -tropin -zolam -zosin

1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 21. 22.

5-HT1B/1D agonist α1 Antagonist ACE inhibitor Antibiotic, protein synthesis inhibitor Antifungal

β antagonist β2 agonist Barbiturate Benzodiazepine Butyrophenone (neuroleptic) Cardiac glycoside (inotropic) Erectile dysfunction H2 antagonist Inhalational general anesthetic Local anesthetic Methylxanthine Penicillin Phenothiazine Pituitary hormone Protease inhibitor SSRI TCA

Answers PHARMACODYNAMICS 1.

Do; do not.

2.

Affinity.

3.

True.

4.

Enzyme concentration.

5.

Increasing.

6.

Km.

7.

A = 1/-Km; B = 1/V max; C = it decreases; D = it increases.

8.

Can; cannot. This is because competitive inhibitors bind the active site of the enzyme, competing with the substrate, whereas noncompetitive inhibitors bind elsewhere on the enzyme and so are not affected by substrate concentration. Copyright © 2011 by MedIQ Learning, LLC

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9.

Do not change; decrease.

10.

Increase; do not change.

11.

Volume of distribution = amount of drug in the body / plasma plasma drug concentration.

12.

Blood alone (these drugs do not distribute outside the plasma); tissue (these drugs distribute throughout the body).

13.

Clearance (L/min) = rate of elimination of drug (g/min) / plasma drug concentration (g/L).

14.

The time required to reduce the amount of drug in the body by one half. half.

15.

Four.

16.

Half-life = (0.7 × volume of distribution) / clearance.

17.

50% of steady-state concentration; 87.5% of steady-state concentration.

18.

Loading dose = (target plasma concentration × volume of distribution) / bioavailability.

19.

Maintenance dose = target plasma concentration × (clearance / bioavailability).

20.

For both diseases, the loading dose does not change, but the maintenance dose dose decreases.

21.

100%.

22.

The rate of elimination is constant, regardless of the drug concentration.

23.

Phenytoin, ethanol, and aspirin (at high or toxic concentrations).

24.

The rate of elimination is directly proportional to the drug concentration. concentration. A constant fraction (rather than a constant amount) is eliminated.

25.

Bicarbonate alkalinizes alkalinizes the lumen of the nephrons, which traps acetylsalicylic acid within the lumen because it is a weak acid and is ionized in a basic environment.

26.

Potent.

27.

A = noncompetitive antagonist; B = competitive antagonist.

28.

Decreases.

29.

A partial agonist has lower maximal efficacy than a full agonist.

30.

A partial agonist may be more potent than, less potent than, or equally as potent as a full agonist.

AUTONOMIC DRUGS 31.

Botulinum toxin prevents the release of neurotransmitter at all cholinergic terminals.

32.

A-2, B-1, C-3, D-3, E-3, F-1, G-2, H-3, I-2, J-1, K-2, L-2, M-3.

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33.

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α1-Receptor activation increases vascular smooth muscle contraction, as well as pupillary dilator muscle contraction (mydriasis).

34.

α2-Receptor activation decreases sympathetic outflow and insulin release.

35.

β1-Receptor activation increases the following: heart rate and contractility; release from the kidneys; and lipolysis of adipose tissue.

36.

Vasodilation; bronchodilation.

37.

β2-Receptor activation increases glucagon release.

38.

(Adapted, with permission, from Katzung BG, Trevor AJ. Pharmacology: Pharmacology: Examination & th Board Review, Review, 5   ed. Stamford, CT: Appleton & Lange, 1998: 42.)

39.

Neostigmine, pyridostigmine, edrophonium, physostigmine, and echothiophate.

40.

Exacerbation of COPD, asthma, and peptic ulcers.

41.

Physostigmine. It crosses the blood-brain barrier and is able to reverse effects on the CNS and the peripheral nervous system.

42.

A test in which methacholine is inhaled to stimulate muscarinic receptors and induce bronchoconstriction. The test is used to diagnose asthma.

43.

This patient has the classic signs of organophosphate organophosphate poisoning, which is treated with atropine and pralidoxime.

44.

Pyridostigmine increases the amount of acetylcholine in the neuromuscular synapse, synapse, thereby increasing muscle strength.

45.

Benztropine.

46.

Pupil dilation and cycloplegia. Copyright © 2011 by MedIQ Learning, LLC

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47.

False. (Constipation is a sign of atropine toxicity.)

48.

β1.

49.

β1 and β2 (equally).

50.

Dopamine is ionotropic and chronotropic; dobutamine is ionotropic but is not chronotropic.

51.

Anaphylaxis, open-angle glaucoma, asthma, and hypotension.

52.

Dopamine increases blood pressure while maintaining renal perfusion.

53.

Phenylephrine treats nasal decongestion, causes vasoconstriction, and dilates pupils.

54.

Acute asthma.

55.

Terbutaline and salmeterol.

56.

Isoproterenol increases pulse pressure and heart rate.

57.

Clonidine is an α2-agonist that decreases central adrenergic outflow. (Remember: responsible for negative feedback).

58.

Phentolamine is a nonselective α -blocker used to treat pheochromocytoma.

59.

Before α-blockade, epinephrine increases blood pressure. After α -blockade, it decreases blood pressure. This is because epinephrine also activates β 2, which lowers blood pressure and is not

the α2-receptor is

blocked. 60.

Suggested. After myocardial infarction, patients patients should receive β -blockers to decrease risk of mortality.

61.

They decrease heart rate and contractility as well as myocardial oxygen consumption.

62.

Pindolol and acebutolol. (Remember: PA = Partial Agonist)

63.

Carvedilol and labetalol.

TOXICITIES AND SIDE EFFECTS 64.

A-12, B-15, C-18, D-9, E-10, F-1, G-19, H-17, I-21, J-20, K-6, L-5, M-7, N-8, O-11, P-16, Q-3, R-14, S-13, T-4, U-2, V-22.

65.

Carbamazepine, colchicine, clozapine, dapsone, methimazole, and propylthiouracil.

66.

Thrombotic complications.

67.

Isoniazid, sulfonamides, primaquine, aspirin, ibuprofen, and nitrofurantoin.

68.

Spironolactone, digitalis, cimetidine, chronic alcohol use, estrogens, and ketoconazole.

69.

Bleomycin, amiodarone, and busulfan.

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70.

Sulfonamides, amiodarone, and tetracycline.

71.

Phenytoin, methotrexate, and sulfa drugs.

72.

Bupropion, imipenem/cilastatin, and isoniazid.

73.

Chlorpromazine, haloperidol, metoclopramide, and reserpine.

74.

Certain cephalosporins, first-generation sulfonylureas, metronidazole, and procarbazine.

75.

Aminoglycosides, cisplatin, loop diuretics, and vancomycin.

76. Substance

P-450 inducer

√

 Alcohol use, acute

Barbiturates

√ √

Carbamazepine

√

 Alcohol use, chronic

P-450 Inhibitor

Cimetidine

√

Erythromycin

√

Grapefruit juice

√

Griseofulvin

√

HIV protease inhibitors

√

Isoniazid

√

Ketoconazole

√

Phenytoin

√

Quinidine

√

Rifampin

√

St. John’s wort

√

Sulfonamides

√

77.

Disulfiram inhibits acetylaldehyde dehydrogenase, which breaks down acetaldehyde. Thus alcohol consumption while taking disulfiram results in nausea, vomiting, headache, and hypotension.

78.

Acetazolamide, celecoxib, furosemide, probenicid, thiazides, TMP-SMX, sulfasalazine, sulfonamide antibiotics, and sulfonylureas.

MISCELLANEOUS 79.

A-12, B-14, C-9, D-18, E-5, F-8, G-15, H-17, I-4, J-21, K-22, L-20, M-6, N-10, O-11, P-16, Q-3, R-7, S-13, T-1, U-22, V-19, W-9, X-2.

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