Pharmacogenetics & Individual Variation — General Pharmacology

Pharmacogenetics & Individual Variation MCQs: practice questions

Sample Pharmacogenetics & Individual Variation multiple-choice questions from General Pharmacology.

1. An older adult receives a renally eliminated drug. Which age-related change may increase drug exposure?

   • A. Increased hepatic enzyme activity in every pathway
   • B. Increased GFR in all older adults
   • C. Increased total body water in all cases
   • D. Complete absence of protein binding
   • E. Reduced renal clearance

2. A patient has decreased renal function and a long half-life for a renally eliminated drug. Which dosing strategy may reduce accumulation?

   • A. Ignore renal function
   • B. Increase the maintenance dose
   • C. Shorten the dosing interval
   • D. Lower dose/longer interval
   • E. Give repeated loading doses

3. Which physiologic change commonly occurs with aging and can alter distribution of lipid-soluble drugs?

   • A. Universal increase in extracellular fluid
   • B. Complete loss of adipose tissue
   • C. Universal increase in total body water
   • D. Universal increase in albumin
   • E. Increased relative body fat

4. A patient is pregnant and requires medication for a serious maternal condition. Which principle is most appropriate?

   • A. Balance maternal and fetal risk
   • B. Ignore gestational timing
   • C. Use the highest dose possible
   • D. Assume fetal exposure is impossible
   • E. Avoid all drugs automatically

5. A patient has a genetic variant that markedly reduces metabolism of a drug by a hepatic enzyme. What is the most likely consequence for a normally active drug?

   • A. No change in exposure
   • B. Lower plasma concentration
   • C. Guaranteed therapeutic failure
   • D. Higher drug concentration
   • E. Increased renal filtration

6. A patient with severe hepatic impairment receives a drug primarily cleared by hepatic metabolism. What may happen?

7. Which factor is most likely to explain why the same dose of a drug produces different responses in two individuals despite similar plasma concentrations?

8. A patient has severe obesity and receives a highly lipid-soluble drug. Which pharmacokinetic parameter may be increased?

9. An ultra-rapid metabolizer receives a prodrug that is activated by the same enzyme. What may occur?

10. A patient's serum albumin is markedly reduced. For a highly albumin-bound drug, what is most likely initially?

11. A patient has both renal impairment and hypoalbuminemia while receiving a highly protein-bound, renally eliminated drug. Why is individualized dosing especially important?

12. A patient with severe renal impairment receives a drug primarily eliminated unchanged in urine. What is most likely?

13. Which patient factor is most likely to require adjustment of a renally eliminated narrow-therapeutic-index drug?

14. Two patients receive the same dose of a drug but have very different plasma concentrations because of inherited differences in metabolism. This illustrates:

15. A patient has reduced hepatic metabolism of an active drug because of a genetic polymorphism. The drug's half-life will most likely:

16. A patient experiences a much stronger effect from a standard dose because of a genetic increase in receptor sensitivity. This is primarily a variation in:

17. A neonate receives a drug primarily eliminated by hepatic metabolism. Compared with an adult, what may occur?

18. A patient has extensive edema. How could this affect a hydrophilic drug?

19. Pregnancy can alter pharmacokinetics through changes in plasma volume, renal function, and body composition. Which is the best prescribing principle?

20. A drug is highly protein bound and has a small therapeutic window. A patient develops hypoalbuminemia. Which concern is most important?

21. A patient develops tolerance to a drug after chronic use because receptor signaling adapts to persistent stimulation. This is:

22. A patient has a genetic polymorphism that changes a receptor but not drug concentration. The most direct consequence is a change in:

23. A drug induces its own hepatic metabolism after prolonged use. This is an example of:

24. A patient is a genetically determined ultra-rapid metabolizer of an active drug. Compared with a normal metabolizer, the patient may have:

25. A patient with chronic kidney disease receives a drug that is eliminated partly by the kidney and partly by the liver. Compared with a drug eliminated entirely by the kidney, this drug may:

26. A patient with advanced liver disease has decreased production of plasma albumin. For a highly albumin-bound drug, the unbound fraction may:

27. Which population may have increased susceptibility to adverse drug effects because drug-metabolizing and renal systems are not fully mature?

28. A patient with a genetic deficiency in a drug-metabolizing enzyme experiences toxicity at a standard dose. The safest response is to:

29. A patient is a poor metabolizer of an enzyme that activates a prodrug. What is most likely?

30. Which factor can increase drug exposure in an older adult even when the prescribed dose is unchanged?