Exam Questions | 100% Correct Answers with Detailed
Rationales (2026/2027 Edition)
Graduate Nursing Advanced Pharmacology for Family Care Midterm Examination
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SECTION 1: Pharmacokinetics, Pharmacodynamics, and Pharmacogenomics
Question 1
A patient with chronic kidney disease (stage 4, eGFR 25 mL/min) is prescribed
metformin 1000 mg twice daily for type 2 diabetes mellitus. Which pharmacokinetic
principle most directly explains the increased risk of lactic acidosis in this patient?
A. Decreased hepatic first-pass metabolism leading to increased bioavailability
B. Reduced renal excretion resulting in drug accumulation and increased plasma
concentration
C. Increased volume of distribution due to altered protein binding in uremia
D. Enhanced hepatic metabolism via CYP2C19 induction in chronic kidney disease
Correct Answer: B
Rationale: Metformin is primarily eliminated unchanged by the kidneys via active tubular
secretion. In stage 4 chronic kidney disease (eGFR <30 mL/min), renal clearance is
significantly impaired, leading to drug accumulation. The FDA has issued a boxed
warning contraindicating metformin use when eGFR falls below 30 mL/min due to the
increased risk of lactic acidosis. Options A, C, and D do not accurately describe the
,primary pharmacokinetic mechanism responsible for metformin toxicity in renal
impairment.
Question 2
A 72-year-old patient taking warfarin 5 mg daily for atrial fibrillation is started on
amiodarone for new-onset ventricular tachycardia. The nurse practitioner recognizes
that this combination significantly increases the risk of bleeding. Which
pharmacodynamic mechanism best explains this interaction?
A. Amiodarone inhibits CYP2C9, reducing warfarin metabolism and increasing its
anticoagulant effect
B. Amiodarone displaces warfarin from albumin binding sites, increasing free warfarin
concentration
C. Amiodarone inhibits CYP3A4 and CYP1A2, reducing warfarin clearance and
potentiating its effect
D. Amiodarone induces P-glycoprotein, increasing warfarin elimination from
hepatocytes
Correct Answer: C
Rationale: Amiodarone is a potent inhibitor of multiple cytochrome P450 enzymes,
including CYP3A4 and CYP1A2, which are involved in the metabolism of both R- and
S-warfarin enantiomers. This inhibition reduces warfarin clearance, leading to increased
plasma concentrations and enhanced anticoagulant effect. While amiodarone can also
inhibit CYP2C9 (Option A), its effects on CYP3A4 and CYP1A2 are more clinically
significant. Option B is incorrect because amiodarone does not significantly displace
warfarin from albumin. Option D is incorrect because amiodarone inhibits, not induces,
P-glycoprotein.
Question 3
,A patient with major depressive disorder is prescribed citalopram 20 mg daily. Genetic
testing reveals the patient is a CYP2C19 poor metabolizer. Which clinical consequence
is most likely?
A. Decreased citalopram efficacy due to rapid metabolism to inactive metabolites
B. Increased risk of citalopram toxicity, including QTc prolongation, due to reduced
clearance
C. Increased risk of serotonin syndrome due to enhanced conversion to
desmethylcitalopram
D. Decreased bioavailability of citalopram due to impaired intestinal absorption
Correct Answer: B
Rationale: Citalopram is primarily metabolized by CYP2C19 and CYP3A4. In CYP2C19
poor metabolizers, citalopram clearance is significantly reduced, leading to increased
plasma concentrations and prolonged exposure. This increases the risk of
dose-dependent adverse effects, particularly QTc prolongation, which has led to an FDA
warning limiting citalopram dosing to 20 mg daily in patients older than 60 years and in
CYP2C19 poor metabolizers. Options A, C, and D do not accurately describe the
pharmacogenomic implications of CYP2C19 poor metabolizer status.
Question 4
A 45-year-old patient with hypertension is prescribed lisinopril 10 mg daily. The nurse
practitioner explains that the drug's antihypertensive effect is primarily achieved
through which pharmacodynamic mechanism?
A. Direct vasodilation of vascular smooth muscle via calcium channel blockade
B. Inhibition of angiotensin-converting enzyme, reducing angiotensin II production and
aldosterone secretion
C. Competitive antagonism of beta-1 adrenergic receptors in the myocardium
D. Inhibition of the sodium-chloride symporter in the distal convoluted tubule
, Correct Answer: B
Rationale: Lisinopril is an angiotensin-converting enzyme (ACE) inhibitor. Its primary
mechanism of action involves inhibiting ACE, which prevents the conversion of
angiotensin I to angiotensin II. This results in decreased vasoconstriction, reduced
aldosterone secretion (leading to decreased sodium and water retention), and increased
bradykinin levels. Option A describes calcium channel blockers, Option C describes
beta-blockers, and Option D describes thiazide diuretics.
Question 5
A pediatric patient weighing 15 kg requires amoxicillin at a dose of 45 mg/kg/day
divided every 12 hours. Which statement regarding pharmacokinetic considerations in
pediatric patients is most accurate?
A. Pediatric patients have decreased gastric emptying time, leading to delayed drug
absorption compared to adults
B. Pediatric patients have a higher proportion of body water and lower proportion of
body fat, resulting in a larger volume of distribution for water-soluble drugs
C. Hepatic enzyme systems are fully mature at birth, resulting in adult-equivalent drug
metabolism rates in neonates
D. Pediatric patients have increased plasma protein binding capacity, leading to
decreased free drug concentrations
Correct Answer: B
Rationale: Pediatric patients, particularly infants and young children, have a higher
percentage of total body water (approximately 70-80% in neonates vs. 50-60% in adults)
and lower body fat percentage. This results in a larger volume of distribution for
water-soluble drugs such as amoxicillin, often necessitating weight-based dosing
adjustments. Option A is incorrect because gastric emptying is actually faster in
children than in adults. Option C is incorrect because hepatic enzyme systems are