What is the antidote for an acetaminophen overdose?

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

Answer: (B)

In acetaminophen overdose, the toxic metabolite NAPQI damages the liver when glutathione is depleted. N-acetylcysteine serves as a precursor to glutathione and helps detoxify NAPQI, protecting liver cells. It can also replenish glutathione stores even after some toxin has formed, making it effective when given as soon as possible—ideally within the first several hours after ingestion.

Activated charcoal can reduce the amount of acetaminophen absorbed if given soon after ingestion, but it is not the antidote to the toxin itself. Naloxone treats opioid overdose, and atropine is used for different toxic or physiologic issues; neither addresses the acetaminophen pathway.

So the best answer is N-acetylcysteine, the specific antidote that neutralizes the toxic effects of acetaminophen by restoring the liver’s detoxification capacity.