NURS6540 ADVANCED
PHARMACOLOGY COMPREHENSIVE
EXAM QUESTIONS AND ANSWERS
1. A patient is prescribed a medication with a half-life of 12 hours. Assuming the drug follows
first-order kinetics and no loading dose is given, how long will it take for the drug to reach
approximately 94% of its steady-state plasma concentration?
A. 24 hours
B. 36 hours
C. 60 hours
D. 48 hours
Answer: D
Conceptual Explanation: It takes approximately 4 to 5 half-lives to reach steady state. 4
half-lives (4 x 12 = 48 hours) achieves 93.75% of steady state.
,2. Which pharmacological phenomenon describes the requirement for increasingly larger
doses of a drug to produce the same effect originally achieved with a smaller dose, often due
to receptor down-regulation?
A. Tachyphylaxis
B. Potentiation
C. Idiosyncratic reaction
D. Tolerance
Answer: D
Conceptual Explanation: Tolerance is a decreased responsiveness to a drug as a result of
repeated administration. Tachyphylaxis is a category of tolerance that occurs very rapidly.
3. A patient with a known CYP2C19 poor metabolizer phenotype is prescribed clopidogrel
(Plavix) following a coronary stent placement. What is the most likely clinical outcome?
A. Increased risk of major bleeding episodes
B. Enhanced antiplatelet activity
C. Increased risk of cardiovascular events due to reduced active metabolite
D. Rapid onset of therapeutic effect
Answer: C
, Conceptual Explanation: Clopidogrel is a prodrug that requires activation by CYP2C19.
Poor metabolizers cannot convert the drug to its active form effectively, leading to
subtherapeutic levels and increased clotting risk.
4. Which of the following best describes the mechanism of action of a non-competitive
antagonist?
A. It binds to the same site as the agonist and can be overcome by increasing agonist
concentration.
B. It mimics the effect of the endogenous ligand but with lower efficacy.
C. It acts as a functional antagonist by activating a different physiological pathway.
D. It binds irreversibly to the receptor site or to an allosteric site, reducing the maximal
response of the agonist.
Answer: D
Conceptual Explanation: Non-competitive antagonists bind in a way that the agonist
cannot displace them, effectively reducing the Emax (maximal effect) regardless of the
agonist concentration.
5. A 65-year-old patient with heart failure is started on Digoxin. Which electrolyte
abnormality significantly increases the risk of digoxin toxicity?
A. Hypokalemia
B. Hyperkalemia
C. Hyponatremia
PHARMACOLOGY COMPREHENSIVE
EXAM QUESTIONS AND ANSWERS
1. A patient is prescribed a medication with a half-life of 12 hours. Assuming the drug follows
first-order kinetics and no loading dose is given, how long will it take for the drug to reach
approximately 94% of its steady-state plasma concentration?
A. 24 hours
B. 36 hours
C. 60 hours
D. 48 hours
Answer: D
Conceptual Explanation: It takes approximately 4 to 5 half-lives to reach steady state. 4
half-lives (4 x 12 = 48 hours) achieves 93.75% of steady state.
,2. Which pharmacological phenomenon describes the requirement for increasingly larger
doses of a drug to produce the same effect originally achieved with a smaller dose, often due
to receptor down-regulation?
A. Tachyphylaxis
B. Potentiation
C. Idiosyncratic reaction
D. Tolerance
Answer: D
Conceptual Explanation: Tolerance is a decreased responsiveness to a drug as a result of
repeated administration. Tachyphylaxis is a category of tolerance that occurs very rapidly.
3. A patient with a known CYP2C19 poor metabolizer phenotype is prescribed clopidogrel
(Plavix) following a coronary stent placement. What is the most likely clinical outcome?
A. Increased risk of major bleeding episodes
B. Enhanced antiplatelet activity
C. Increased risk of cardiovascular events due to reduced active metabolite
D. Rapid onset of therapeutic effect
Answer: C
, Conceptual Explanation: Clopidogrel is a prodrug that requires activation by CYP2C19.
Poor metabolizers cannot convert the drug to its active form effectively, leading to
subtherapeutic levels and increased clotting risk.
4. Which of the following best describes the mechanism of action of a non-competitive
antagonist?
A. It binds to the same site as the agonist and can be overcome by increasing agonist
concentration.
B. It mimics the effect of the endogenous ligand but with lower efficacy.
C. It acts as a functional antagonist by activating a different physiological pathway.
D. It binds irreversibly to the receptor site or to an allosteric site, reducing the maximal
response of the agonist.
Answer: D
Conceptual Explanation: Non-competitive antagonists bind in a way that the agonist
cannot displace them, effectively reducing the Emax (maximal effect) regardless of the
agonist concentration.
5. A 65-year-old patient with heart failure is started on Digoxin. Which electrolyte
abnormality significantly increases the risk of digoxin toxicity?
A. Hypokalemia
B. Hyperkalemia
C. Hyponatremia
