NAPQI's an acronym for the chemical N-acetyl-p-benzo-quinone imine. It's a toxic byproduct produced during the xenobiotic metabolism of the analgesic paracetamol (also called acetaminophen). It's normally produced only in small amounts, and then almost immediately detoxified in the liver. However, under some conditions in which NAPQI isn't effectively detoxified (usually in case of paracetamol overdose), it causes severe damage to the liver. This becomes apparent after 3–4 days after ing… (More on Napqi)