[Acute acetaminophen overdose]

Abstract

Acute ingestion of acetaminophen can induce a dose-dependent hepatotoxicity and lead to death. The management of acute acetaminophen poisoning at the early stage is well codified. A reported amount of ingestion > 200 mg/kg in a child, > 150 mg/kg in an adult (125 mg/kg if risk factors are present) require hospitalisation. Activated charcoal is administered within 1-2 hours of ingestion. AST/ALT levels are measured on admission, 12 hours after, and according to outcome every 12-24 h. N-acetylcysteine (NAC) administration within 8-10 hours protects against acetaminophen-induced hepatotoxicity. The two protocols of NAC administration, intravenous and oral, have a comparable effectiveness. NAC is indicated if the serum acetaminophen level drawn 4 hours after ingestion and plotted on the nomograme falls above the "200 mg/L-4 hours" line. Nomograme is not usable with repeated acute ingestion or repeated supratherapeutic doses; presence of risk factors (enzymatic induction, malnutrition, chronic alcoholism) must be taken into account ("100 mg/L - 4 hours" line). Outcome is favorable with respect to these conditions.