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Acetaminophen overdose — USMLE Step 3 MCQ

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ModerateEmergency MedicineAcetaminophen overdoseUSMLE Step 3

A 22-year-old woman presents 6 hours after taking an unknown quantity of acetaminophen. She is nauseated but alert. AST and ALT are normal. Serum acetaminophen level is above the treatment line on the Rumack-Matthew nomogram. Which of the following is the most appropriate next step in management?

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Correct answer: A — Start N-acetylcysteine

N-acetylcysteine prevents hepatotoxicity after toxic acetaminophen ingestion and should be given based on nomogram risk or uncertain high-risk timing.

Reference: American College of Medical Toxicology Acetaminophen Guidance