What is the antidote for acetaminophen overdose?

• A. N-acetylcysteine
• B. Activated charcoal
• C. Penicillamine
• D. Naloxone

Answer: (A)

Acetaminophen overdose causes liver injury when the toxic metabolite NAPQI builds up because hepatic glutathione is depleted. N-acetylcysteine serves as a precursor to glutathione, supplying the cysteine needed to replenish glutathione stores. With glutathione restored, NAPQI can be detoxified through conjugation and safely excreted, preventing hepatocellular damage. Administering this antidote promptly is crucial and can be life-saving, with options for oral or intravenous administration depending on the situation.

Activated charcoal can reduce absorption if given very soon after ingestion, but it is not an antidote. Penicillamine is used for copper chelation, not acetaminophen toxicity. Naloxone reverses opioid effects, not acetaminophen overdose.