Which antidote is used for treating acetaminophen overdose?

N-acetylcysteine is the specific antidote for acetaminophen overdose and works by replenishing glutathione levels in the liver, which helps to detoxify the harmful metabolite, N-acetyl-p-benzoquinone imine (NAPQI), that is produced when acetaminophen is taken in excessive amounts. The timing of administration is critical; N-acetylcysteine is most effective when given within 8 to 10 hours following the overdose, although it can still be beneficial beyond this time frame. It acts by conjugating with NAPQI, thus minimizing liver injury and potential fulminant hepatic failure, which is a severe complication of acetaminophen toxicity.

This specific mechanism of action directly addresses the underlying biochemical processes involved in acetaminophen overdose, making N-acetylcysteine an essential treatment in clinical practice. Other treatment modalities may aid in the management of overdose symptoms, but they do not have the same specific effect on the detoxification of acetaminophen.