NAPLEX QBANK Naplex Qbank/Questions/Practice 1

Question 1

A patient with a CrCl of 28 mL/min is currently taking metformin 1000 mg twice daily for type 2 diabetes. What is the most appropriate action?

Accepted Answer

Discontinue metformin due to risk of lactic acidosis

Answer

Metformin is contraindicated when CrCl falls below 30 mL/min because impaired renal clearance leads to drug accumulation and a dangerous risk of lactic acidosis. Dose reduction is not sufficient at this level — the drug must be discontinued.

Question 2

Which antipsychotic medication requires mandatory enrollment in a Risk Evaluation and Mitigation Strategy (REMS) program due to the risk of severe agranulocytosis?

Accepted Answer

Clozapine

Answer

Clozapine carries a black box warning for potentially fatal agranulocytosis and requires the Clozapine REMS Program, which mandates ANC monitoring before dispensing. No other antipsychotic has this requirement.

Question 3

A 58-year-old patient is started on isoniazid (INH) for latent tuberculosis. Which supplement should routinely be co-administered to prevent a common dose-dependent adverse effect?

Accepted Answer

Vitamin B6 (pyridoxine)

Answer

INH inhibits pyridoxine (B6) metabolism, which can lead to peripheral neuropathy, particularly in high-risk groups (elderly, malnourished, diabetic, pregnant). Pyridoxine 25–50 mg daily is co-prescribed to prevent this toxicity.

Question 4

A patient with a history of bilateral renal artery stenosis presents with newly diagnosed hypertension. Which antihypertensive class is most likely to precipitate acute renal failure in this patient?

Accepted Answer

ACE inhibitors

Answer

In bilateral renal artery stenosis, perfusion of both kidneys depends on angiotensin II–mediated efferent arteriolar constriction. ACE inhibitors block this compensatory mechanism, causing a sharp drop in GFR and acute kidney injury.

Question 5

A pharmacist is reviewing vancomycin therapy for a hospitalized patient with MRSA bacteremia. According to current ASHP/IDSA/SIDP consensus guidelines, which monitoring approach is now preferred over trough-only monitoring?

Accepted Answer

AUC/MIC ratio-guided monitoring combined with serum creatinine

Answer

Current consensus guidelines (2020) replaced trough-only monitoring with AUC/MIC-guided monitoring (target AUC 400–600 mg·h/L), as it better predicts efficacy and reduces nephrotoxicity risk compared to targeting high trough levels.

NAPLEX QBANK Practice Test

NAPLEX QBANK Practice Test

NAPLEX QBANK Naplex Qbank/Questions/Practice 1