Drug Interactions & Adverse Drug Reactions — General Pharmacology

Drug Interactions & Adverse Drug Reactions MCQs: practice questions

Sample Drug Interactions & Adverse Drug Reactions multiple-choice questions from General Pharmacology.

1. Which patient is at greatest risk of toxicity from a drug eliminated predominantly by the kidneys?

   • A. A healthy young adult
   • B. A patient with severe renal impairment
   • C. A patient with increased GFR
   • D. A patient with mild hyperventilation
   • E. A patient with increased hepatic blood flow

2. A patient taking a drug develops reduced responsiveness because receptor number or signaling adapts during chronic exposure. This is:

   • A. First-pass effect
   • B. Metabolic tolerance
   • C. Cellular tolerance
   • D. Renal clearance
   • E. Bioavailability

3. A patient taking two drugs experiences a greater-than-additive therapeutic effect. This is:

   • A. First-pass effect
   • B. Antagonism
   • C. Idiosyncrasy
   • D. Tolerance
   • E. Synergism

4. Two drugs compete for the same renal tubular secretion transporter. What type of interaction is this?

   • A. Therapeutic index interaction
   • B. Pharmacodynamic receptor interaction
   • C. Allergic interaction
   • D. Altered elimination
   • E. Placebo effect

5. Which adverse effect is most likely to be dose-dependent and predictable from the known pharmacology of a drug?

   • A. An unexpected immune reaction
   • B. Exaggerated pharmacologic effect
   • C. A rare genetic hypersensitivity
   • D. An idiosyncratic liver injury
   • E. A delayed teratogenic effect only

6. A drug is known to inhibit CYP3A. Which outcome is most likely for a second drug that is normally metabolized by CYP3A?

7. A patient taking multiple medications develops toxicity because one medication inhibits renal secretion of another. The affected drug's clearance will most likely:

8. A patient taking a sedative and an opioid develops severe respiratory depression. The interaction is most consistent with:

9. A drug causes gastric irritation and dizziness at doses above those needed for its therapeutic effect. These effects are best classified as:

10. A drug increases the toxicity of another drug by slowing its hepatic metabolism. This is best classified as:

11. A patient taking a medication develops a rash only after repeated exposure, with evidence of an immune-mediated delayed response. This is most consistent with:

12. Which interaction would most directly increase a drug's steady-state concentration if dosing rate is unchanged?

13. A patient taking an oral drug develops toxicity after starting an antacid that increases gastric pH and alters drug absorption. This is an interaction affecting:

14. A drug directly binds and inactivates another drug in the gastrointestinal tract, preventing its absorption. This is:

15. A patient develops wheezing, urticaria, hypotension, and airway swelling immediately after receiving a medication. This is most consistent with:

16. A patient develops severe diarrhea after an antibiotic because the drug's concentration in the intestinal lumen remains high. This adverse effect is most closely related to:

17. A patient takes a drug that induces its own metabolism over time. Which form of tolerance is demonstrated?

18. A patient receiving a narrow-therapeutic-index drug develops toxicity after a second medication displaces it from plasma proteins. What is the immediate pharmacokinetic change?

19. A patient repeatedly takes a drug and requires progressively larger doses to achieve the same effect. This is:

20. A patient taking warfarin begins a drug that inhibits hepatic cytochrome P-450 metabolism of warfarin. What is most likely?

21. A patient becomes physically dependent on a drug. Abrupt discontinuation produces a characteristic withdrawal syndrome. Which statement is correct?

22. A patient experiences a serious adverse reaction after a medication dose, but the reaction is unrelated to the drug's therapeutic mechanism and cannot be predicted from dose. This most closely fits:

23. A patient taking an inactive prodrug begins a potent enzyme inhibitor that blocks its conversion to the active metabolite. What happens?

24. A patient receives two drugs that bind different receptors but produce opposing effects on the same physiologic variable. This is:

25. Chronic administration of a drug induces CYP3A enzymes that metabolize another medication. What is the expected effect on the second drug?

26. A patient develops severe hepatic injury after prolonged exposure to a medication. The reaction is unpredictable and unrelated to the usual pharmacologic effect. This is best termed:

27. Which cytochrome P-450 subfamily accounts for a large fraction of clinically important metabolic drug interactions?

28. A patient taking two drugs develops toxicity because both drugs depress the same physiologic function. This is best described as a:

29. A patient with liver disease receives a drug with extensive first-pass hepatic metabolism. What change may occur?

30. A patient develops tolerance to one drug and partial tolerance to another drug in the same class. This is called: