NSG533 Exam 1 Actual Exam 2026/2027 – Advanced
Pharmacology Questions with Detailed Rationales | 100%
Verified | Pass Guaranteed – A+ Graded
SECTION 1: Pharmacokinetics & Pharmacodynamics (Q1-Q15)
Q1: A 72-year-old male with atrial fibrillation is started on digoxin 0.25 mg daily. He is
also prescribed amiodarone for rhythm control. The nurse practitioner should recognize
which pharmacokinetic interaction?
A. Amiodarone induces CYP3A4, decreasing digoxin levels.
B. Amiodarone inhibits P-glycoprotein, increasing digoxin levels. [CORRECT]
C. Amiodarone increases digoxin renal clearance via tubular secretion.
D. Amiodarone displaces digoxin from alpha-1 acid glycoprotein binding sites.
Correct Answer: B
Rationale: Amiodarone inhibits P-glycoprotein (an efflux transporter in the GI tract and
kidneys), which increases digoxin bioavailability and decreases its renal elimination.
This raises digoxin levels and increases toxicity risk. Digoxin has a narrow therapeutic
index (0.8-2.0 ng/mL), so levels should be monitored closely when amiodarone is
added. [100% VERIFIED – Wilkes NSG533]
Q2: A patient with epilepsy on carbamazepine is started on oral contraceptives. The
nurse practitioner counsels the patient that:
A. Carbamazepine inhibits CYP3A4, increasing estrogen levels and thrombosis risk.
B. Carbamazepine induces CYP3A4, decreasing contraceptive efficacy and increasing
pregnancy risk. [CORRECT]
C. Carbamazepine displaces progestin from albumin, enhancing contraceptive effect.
D. Carbamazepine inhibits glucuronidation, prolonging progestin half-life.
Correct Answer: B
Rationale: Carbamazepine is a potent CYP3A4 inducer that increases metabolism of
estrogen and progestin components in oral contraceptives, reducing their efficacy.
Patients should use alternative or backup contraception. This is a classic enzyme
induction interaction. [100% VERIFIED – Wilkes NSG533]
,Q3: A 68-year-old female with heart failure is prescribed lisinopril. She reports using
ibuprofen regularly for arthritis. The nurse practitioner explains the primary concern is:
A. Ibuprofen inhibits ACE, reducing lisinopril efficacy.
B. NSAIDs reduce prostaglandin-mediated renal vasodilation, causing acute kidney
injury and hyperkalemia with ACE inhibitors. [CORRECT]
C. Ibuprofen increases lisinopril absorption via enhanced gastric emptying.
D. NSAIDs induce CYP2C9, increasing lisinopril metabolism.
Correct Answer: B
Rationale: NSAIDs inhibit prostaglandin synthesis, which normally maintains renal
perfusion through vasodilation. Combined with ACE inhibitors (which also affect renal
hemodynamics), this significantly increases risk of acute kidney injury, hyperkalemia,
and fluid retention. [100% VERIFIED – Wilkes NSG533]
Q4: A patient on warfarin (INR 2.5) is started on trimethoprim-sulfamethoxazole for a
UTI. The nurse practitioner should anticipate:
A. TMP-SMX induces CYP2C9, requiring increased warfarin dosing.
B. TMP-SMX inhibits CYP2C9 and displaces warfarin from albumin, increasing bleeding
risk. [CORRECT]
C. TMP-SMX increases vitamin K absorption, antagonizing warfarin effect.
D. TMP-SMX enhances warfarin renal excretion, decreasing INR.
Correct Answer: B
Rationale: TMP-SMX inhibits CYP2C9 (the primary enzyme metabolizing S-warfarin) and
displaces warfarin from albumin binding sites, increasing free warfarin concentration.
This potentiates anticoagulant effect and increases bleeding risk. INR should be
monitored closely. [100% VERIFIED – Wilkes NSG533]
Q5: A 55-year-old male with liver cirrhosis is prescribed lorazepam for alcohol
withdrawal. The rationale for choosing lorazepam over diazepam is:
A. Lorazepam undergoes Phase I oxidation via CYP3A4, which is preserved in cirrhosis.
B. Lorazepam undergoes Phase II glucuronidation, which is relatively preserved in
hepatic impairment. [CORRECT]
C. Lorazepam is a prodrug activated by hepatic first-pass metabolism.
D. Lorazepam has a larger volume of distribution, minimizing hepatic exposure.
Correct Answer: B
Rationale: Lorazepam is metabolized via glucuronidation (Phase II), which is less
affected by hepatic impairment compared to oxidation (Phase I). Diazepam undergoes
,extensive Phase I metabolism via CYP2C19 and CYP3A4, which is significantly impaired
in cirrhosis, leading to prolonged half-life and accumulation. [100% VERIFIED – Wilkes
NSG533]
Q6: A patient receiving gentamicin has a peak level of 12 mcg/mL and trough of 3
mcg/mL. Based on pharmacokinetic principles, the nurse practitioner determines:
A. Levels are therapeutic; no dose adjustment needed.
B. The trough is too high, indicating accumulation and increased nephrotoxicity risk.
[CORRECT]
C. The peak is subtherapeutic; the dose should be increased.
D. Gentamicin follows zero-order kinetics at these concentrations.
Correct Answer: B
Rationale: For gentamicin, target trough is typically <2 mcg/mL (or <1 mcg/mL for
extended-interval dosing). A trough of 3 mcg/mL indicates drug accumulation, which
increases risk of nephrotoxicity and ototoxicity. The dose should be extended or
reduced. Aminoglycosides exhibit concentration-dependent killing and follow first-order
kinetics. [100% VERIFIED – Wilkes NSG533]
Q7: A 45-year-old female with depression is prescribed fluoxetine. She has been taking
tamoxifen for breast cancer prevention. The nurse practitioner's greatest concern is:
A. Fluoxetine inhibits CYP2D6, reducing conversion of tamoxifen to its active metabolite
endoxifen. [CORRECT]
B. Fluoxetine induces CYP3A4, increasing tamoxifen metabolism.
C. Fluoxetine displaces tamoxifen from alpha-1 acid glycoprotein, increasing toxicity.
D. Fluoxetine increases tamoxifen absorption via delayed gastric emptying.
Correct Answer: A
Rationale: Tamoxifen is a prodrug requiring CYP2D6-mediated conversion to endoxifen
for efficacy. Fluoxetine (and paroxetine) are potent CYP2D6 inhibitors that significantly
reduce endoxifen levels, potentially compromising tamoxifen's antiestrogenic effect.
Alternative antidepressants with minimal CYP2D6 inhibition should be considered.
[100% VERIFIED – Wilkes NSG533]
Q8: A patient with a history of organ transplant on cyclosporine drinks grapefruit juice
daily. The nurse practitioner explains that grapefruit juice:
, A. Induces CYP3A4 in the intestinal wall, decreasing cyclosporine levels.
B. Inhibits intestinal CYP3A4 and P-glycoprotein, increasing cyclosporine bioavailability.
[CORRECT]
C. Enhances cyclosporine renal excretion via tubular secretion.
D. Displaces cyclosporine from albumin, increasing free fraction.
Correct Answer: B
Rationale: Grapefruit juice contains furanocoumarins that irreversibly inhibit intestinal
CYP3A4 and P-glycoprotein for 24-72 hours. This increases bioavailability of CYP3A4
substrates like cyclosporine, potentially causing toxicity. The effect is primarily
intestinal, not hepatic. [100% VERIFIED – Wilkes NSG533]
Q9: A 60-year-old male with hypertension is prescribed propranolol for migraine
prophylaxis. He also has COPD. The nurse practitioner's primary concern is:
A. Propranolol is a non-selective beta-blocker that can cause bronchospasm in COPD
patients. [CORRECT]
B. Propranolol selectively blocks beta-1 receptors, sparing bronchial beta-2 receptors.
C. Propranolol induces CYP2D6, reducing theophylline levels if used.
D. Propranolol increases airway inflammation via prostaglandin inhibition.
Correct Answer: A
Rationale: Propranolol is a non-selective beta-blocker that antagonizes beta-2 receptors
in bronchial smooth muscle, potentially causing bronchospasm and exacerbating
COPD/asthma. Cardioselective beta-blockers (metoprolol, atenolol) are preferred in
patients with reactive airway disease. [100% VERIFIED – Wilkes NSG533]
Q10: A patient on phenytoin for seizures is found to have subtherapeutic levels despite
good adherence. The patient recently started rifampin for TB prophylaxis. The
mechanism is:
A. Rifampin inhibits CYP2C9, decreasing phenytoin metabolism.
B. Rifampin induces multiple CYP450 enzymes, increasing phenytoin clearance.
[CORRECT]
C. Rifampin displaces phenytoin from albumin, increasing free fraction excretion.
D. Rifampin inhibits phenytoin absorption via chelation.
Correct Answer: B
Rationale: Rifampin is a broad-spectrum CYP450 inducer (CYP2C9, CYP3A4, CYP2C19)
that increases metabolism of many drugs including phenytoin. This decreases
Pharmacology Questions with Detailed Rationales | 100%
Verified | Pass Guaranteed – A+ Graded
SECTION 1: Pharmacokinetics & Pharmacodynamics (Q1-Q15)
Q1: A 72-year-old male with atrial fibrillation is started on digoxin 0.25 mg daily. He is
also prescribed amiodarone for rhythm control. The nurse practitioner should recognize
which pharmacokinetic interaction?
A. Amiodarone induces CYP3A4, decreasing digoxin levels.
B. Amiodarone inhibits P-glycoprotein, increasing digoxin levels. [CORRECT]
C. Amiodarone increases digoxin renal clearance via tubular secretion.
D. Amiodarone displaces digoxin from alpha-1 acid glycoprotein binding sites.
Correct Answer: B
Rationale: Amiodarone inhibits P-glycoprotein (an efflux transporter in the GI tract and
kidneys), which increases digoxin bioavailability and decreases its renal elimination.
This raises digoxin levels and increases toxicity risk. Digoxin has a narrow therapeutic
index (0.8-2.0 ng/mL), so levels should be monitored closely when amiodarone is
added. [100% VERIFIED – Wilkes NSG533]
Q2: A patient with epilepsy on carbamazepine is started on oral contraceptives. The
nurse practitioner counsels the patient that:
A. Carbamazepine inhibits CYP3A4, increasing estrogen levels and thrombosis risk.
B. Carbamazepine induces CYP3A4, decreasing contraceptive efficacy and increasing
pregnancy risk. [CORRECT]
C. Carbamazepine displaces progestin from albumin, enhancing contraceptive effect.
D. Carbamazepine inhibits glucuronidation, prolonging progestin half-life.
Correct Answer: B
Rationale: Carbamazepine is a potent CYP3A4 inducer that increases metabolism of
estrogen and progestin components in oral contraceptives, reducing their efficacy.
Patients should use alternative or backup contraception. This is a classic enzyme
induction interaction. [100% VERIFIED – Wilkes NSG533]
,Q3: A 68-year-old female with heart failure is prescribed lisinopril. She reports using
ibuprofen regularly for arthritis. The nurse practitioner explains the primary concern is:
A. Ibuprofen inhibits ACE, reducing lisinopril efficacy.
B. NSAIDs reduce prostaglandin-mediated renal vasodilation, causing acute kidney
injury and hyperkalemia with ACE inhibitors. [CORRECT]
C. Ibuprofen increases lisinopril absorption via enhanced gastric emptying.
D. NSAIDs induce CYP2C9, increasing lisinopril metabolism.
Correct Answer: B
Rationale: NSAIDs inhibit prostaglandin synthesis, which normally maintains renal
perfusion through vasodilation. Combined with ACE inhibitors (which also affect renal
hemodynamics), this significantly increases risk of acute kidney injury, hyperkalemia,
and fluid retention. [100% VERIFIED – Wilkes NSG533]
Q4: A patient on warfarin (INR 2.5) is started on trimethoprim-sulfamethoxazole for a
UTI. The nurse practitioner should anticipate:
A. TMP-SMX induces CYP2C9, requiring increased warfarin dosing.
B. TMP-SMX inhibits CYP2C9 and displaces warfarin from albumin, increasing bleeding
risk. [CORRECT]
C. TMP-SMX increases vitamin K absorption, antagonizing warfarin effect.
D. TMP-SMX enhances warfarin renal excretion, decreasing INR.
Correct Answer: B
Rationale: TMP-SMX inhibits CYP2C9 (the primary enzyme metabolizing S-warfarin) and
displaces warfarin from albumin binding sites, increasing free warfarin concentration.
This potentiates anticoagulant effect and increases bleeding risk. INR should be
monitored closely. [100% VERIFIED – Wilkes NSG533]
Q5: A 55-year-old male with liver cirrhosis is prescribed lorazepam for alcohol
withdrawal. The rationale for choosing lorazepam over diazepam is:
A. Lorazepam undergoes Phase I oxidation via CYP3A4, which is preserved in cirrhosis.
B. Lorazepam undergoes Phase II glucuronidation, which is relatively preserved in
hepatic impairment. [CORRECT]
C. Lorazepam is a prodrug activated by hepatic first-pass metabolism.
D. Lorazepam has a larger volume of distribution, minimizing hepatic exposure.
Correct Answer: B
Rationale: Lorazepam is metabolized via glucuronidation (Phase II), which is less
affected by hepatic impairment compared to oxidation (Phase I). Diazepam undergoes
,extensive Phase I metabolism via CYP2C19 and CYP3A4, which is significantly impaired
in cirrhosis, leading to prolonged half-life and accumulation. [100% VERIFIED – Wilkes
NSG533]
Q6: A patient receiving gentamicin has a peak level of 12 mcg/mL and trough of 3
mcg/mL. Based on pharmacokinetic principles, the nurse practitioner determines:
A. Levels are therapeutic; no dose adjustment needed.
B. The trough is too high, indicating accumulation and increased nephrotoxicity risk.
[CORRECT]
C. The peak is subtherapeutic; the dose should be increased.
D. Gentamicin follows zero-order kinetics at these concentrations.
Correct Answer: B
Rationale: For gentamicin, target trough is typically <2 mcg/mL (or <1 mcg/mL for
extended-interval dosing). A trough of 3 mcg/mL indicates drug accumulation, which
increases risk of nephrotoxicity and ototoxicity. The dose should be extended or
reduced. Aminoglycosides exhibit concentration-dependent killing and follow first-order
kinetics. [100% VERIFIED – Wilkes NSG533]
Q7: A 45-year-old female with depression is prescribed fluoxetine. She has been taking
tamoxifen for breast cancer prevention. The nurse practitioner's greatest concern is:
A. Fluoxetine inhibits CYP2D6, reducing conversion of tamoxifen to its active metabolite
endoxifen. [CORRECT]
B. Fluoxetine induces CYP3A4, increasing tamoxifen metabolism.
C. Fluoxetine displaces tamoxifen from alpha-1 acid glycoprotein, increasing toxicity.
D. Fluoxetine increases tamoxifen absorption via delayed gastric emptying.
Correct Answer: A
Rationale: Tamoxifen is a prodrug requiring CYP2D6-mediated conversion to endoxifen
for efficacy. Fluoxetine (and paroxetine) are potent CYP2D6 inhibitors that significantly
reduce endoxifen levels, potentially compromising tamoxifen's antiestrogenic effect.
Alternative antidepressants with minimal CYP2D6 inhibition should be considered.
[100% VERIFIED – Wilkes NSG533]
Q8: A patient with a history of organ transplant on cyclosporine drinks grapefruit juice
daily. The nurse practitioner explains that grapefruit juice:
, A. Induces CYP3A4 in the intestinal wall, decreasing cyclosporine levels.
B. Inhibits intestinal CYP3A4 and P-glycoprotein, increasing cyclosporine bioavailability.
[CORRECT]
C. Enhances cyclosporine renal excretion via tubular secretion.
D. Displaces cyclosporine from albumin, increasing free fraction.
Correct Answer: B
Rationale: Grapefruit juice contains furanocoumarins that irreversibly inhibit intestinal
CYP3A4 and P-glycoprotein for 24-72 hours. This increases bioavailability of CYP3A4
substrates like cyclosporine, potentially causing toxicity. The effect is primarily
intestinal, not hepatic. [100% VERIFIED – Wilkes NSG533]
Q9: A 60-year-old male with hypertension is prescribed propranolol for migraine
prophylaxis. He also has COPD. The nurse practitioner's primary concern is:
A. Propranolol is a non-selective beta-blocker that can cause bronchospasm in COPD
patients. [CORRECT]
B. Propranolol selectively blocks beta-1 receptors, sparing bronchial beta-2 receptors.
C. Propranolol induces CYP2D6, reducing theophylline levels if used.
D. Propranolol increases airway inflammation via prostaglandin inhibition.
Correct Answer: A
Rationale: Propranolol is a non-selective beta-blocker that antagonizes beta-2 receptors
in bronchial smooth muscle, potentially causing bronchospasm and exacerbating
COPD/asthma. Cardioselective beta-blockers (metoprolol, atenolol) are preferred in
patients with reactive airway disease. [100% VERIFIED – Wilkes NSG533]
Q10: A patient on phenytoin for seizures is found to have subtherapeutic levels despite
good adherence. The patient recently started rifampin for TB prophylaxis. The
mechanism is:
A. Rifampin inhibits CYP2C9, decreasing phenytoin metabolism.
B. Rifampin induces multiple CYP450 enzymes, increasing phenytoin clearance.
[CORRECT]
C. Rifampin displaces phenytoin from albumin, increasing free fraction excretion.
D. Rifampin inhibits phenytoin absorption via chelation.
Correct Answer: B
Rationale: Rifampin is a broad-spectrum CYP450 inducer (CYP2C9, CYP3A4, CYP2C19)
that increases metabolism of many drugs including phenytoin. This decreases
