N-acetyl-p-benzoquinone imine (NAPQI) is a highly reactive metabolite of acetaminophen (paracetamol), a commonly used over-the-counter analgesic and antipyretic medication. Under normal circumstances, acetaminophen is primarily metabolized in the liver through conjugation with sulfate and glucuronide. However, a small fraction is metabolized by the cytochrome P450 enzyme system, particularly CYP2E1, to produce NAPQI.
