Paracetamol poisoning (acetaminophen toxicity), first described in the 1960s, occurs from an overdose and damages the liver through the toxic metabolite NAPQI, which depletes glutathione and directly injures liver cells. Symptoms progress through three phases: initial mild nausea and fatigue, a brief period of apparent improvement, and then severe liver failure marked by jaundice, bleeding problems, and confusion, with death possible 4 to 18 days later if untreated. Diagnosis relies on blood paracetamol levels plotted on the Rumack-Matthew nomogram, while treatment includes activated charcoal if given early and the antidote acetylcysteine, with a liver transplant required in severe cases. Risk factors include alcoholism and malnutrition, and although early treatment makes liver failure rare, death occurs in about 0.1% of cases, with most people recovering fully within weeks. It is a major public health issue—over 100,000 cases occur annually in the US, and it is the most common cause of acute liver failure in both the US and UK.