NR 508 ADVANCED PHARMACOLOGY
EXAM PREP QUESTIONS AND
ANSWERS
1. A patient is taking a drug with a short half-life of 4 hours. How many hours will it take for
the drug to reach steady-state concentration in the plasma?
A. 16 to 20 hours
B. 8 to 12 hours
C. 24 to 32 hours
D. 40 to 48 hours
Answer: A
Conceptual Explanation: Steady-state is generally reached after 4 to 5 half-lives. For a
drug with a 4-hour half-life, 4 x 4 = 16 and 5 x 4 = 20 hours.
2. Which cytochrome P450 enzyme is responsible for the metabolism of approximately 50
percent of all clinically used drugs?
A. CYP2D6
B. CYP1A2
,C. CYP2C19
D. CYP3A4
Answer: D
Conceptual Explanation: CYP3A4 is the most abundant and clinically significant
cytochrome P450 enzyme, metabolizing about half of all currently prescribed medications.
3. A patient on Clopidogrel (Plavix) should avoid Omeprazole (Prilosec) because of which
mechanism?
A. Omeprazole induces CYP3A4, leading to drug toxicity
B. Omeprazole inhibits CYP2C19, preventing the activation of Clopidogrel
C. Clopidogrel increases the risk of GI bleeding when combined with PPIs
D. The combination causes severe hyperkalemia
Answer: B
Conceptual Explanation: Clopidogrel is a prodrug that requires activation by CYP2C19.
Omeprazole inhibits this enzyme, reducing the antiplatelet effect of Clopidogrel.
4. When switching a patient from an ACE inhibitor to Sacubitril/Valsartan (Entresto), what is
the required washout period?
A. 12 hours
B. 24 hours
C. 48 hours
, D. 36 hours
Answer: D
Conceptual Explanation: A 36-hour washout period is required when transitioning from
an ACEI to Entresto to minimize the risk of angioedema.
5. Which medication is most likely to cause drug-induced lupus erythematosus (DILE)?
A. Hydralazine
B. Atenolol
C. Lisinopril
D. Hydrochlorothiazide
Answer: A
Conceptual Explanation: Hydralazine is a classic cause of drug-induced lupus, especially
in slow acetylators.
6. Which of the following is a potential side effect of long-term Proton Pump Inhibitor (PPI)
use?
A. Vitamin B12 deficiency
B. Hyponatremia
C. Hypokalemia
D. Hypercalcemia
EXAM PREP QUESTIONS AND
ANSWERS
1. A patient is taking a drug with a short half-life of 4 hours. How many hours will it take for
the drug to reach steady-state concentration in the plasma?
A. 16 to 20 hours
B. 8 to 12 hours
C. 24 to 32 hours
D. 40 to 48 hours
Answer: A
Conceptual Explanation: Steady-state is generally reached after 4 to 5 half-lives. For a
drug with a 4-hour half-life, 4 x 4 = 16 and 5 x 4 = 20 hours.
2. Which cytochrome P450 enzyme is responsible for the metabolism of approximately 50
percent of all clinically used drugs?
A. CYP2D6
B. CYP1A2
,C. CYP2C19
D. CYP3A4
Answer: D
Conceptual Explanation: CYP3A4 is the most abundant and clinically significant
cytochrome P450 enzyme, metabolizing about half of all currently prescribed medications.
3. A patient on Clopidogrel (Plavix) should avoid Omeprazole (Prilosec) because of which
mechanism?
A. Omeprazole induces CYP3A4, leading to drug toxicity
B. Omeprazole inhibits CYP2C19, preventing the activation of Clopidogrel
C. Clopidogrel increases the risk of GI bleeding when combined with PPIs
D. The combination causes severe hyperkalemia
Answer: B
Conceptual Explanation: Clopidogrel is a prodrug that requires activation by CYP2C19.
Omeprazole inhibits this enzyme, reducing the antiplatelet effect of Clopidogrel.
4. When switching a patient from an ACE inhibitor to Sacubitril/Valsartan (Entresto), what is
the required washout period?
A. 12 hours
B. 24 hours
C. 48 hours
, D. 36 hours
Answer: D
Conceptual Explanation: A 36-hour washout period is required when transitioning from
an ACEI to Entresto to minimize the risk of angioedema.
5. Which medication is most likely to cause drug-induced lupus erythematosus (DILE)?
A. Hydralazine
B. Atenolol
C. Lisinopril
D. Hydrochlorothiazide
Answer: A
Conceptual Explanation: Hydralazine is a classic cause of drug-induced lupus, especially
in slow acetylators.
6. Which of the following is a potential side effect of long-term Proton Pump Inhibitor (PPI)
use?
A. Vitamin B12 deficiency
B. Hyponatremia
C. Hypokalemia
D. Hypercalcemia
