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Clinical manifestations and diagnosis of acetaminophen (paracetamol) poisoning in children and adolescents

Kennon Heard, MD
Richard Dart, MD, PhD
Section Editor
Michele M Burns, MD, MPH
Deputy Editor
James F Wiley, II, MD, MPH


Since its clinical introduction in 1950, acetaminophen (N-acetyl-p-aminophenol; APAP; paracetamol) has become the most widely used analgesic and antipyretic in the United States. The popularity of acetaminophen among pediatricians increased when concerns were raised about an association between aspirin and Reye syndrome.

Acetaminophen is available in hundreds of over-the-counter and prescription medications. Although it is remarkably safe when used at therapeutic doses, overdose of acetaminophen has been recognized to cause fatal and nonfatal hepatic necrosis since 1966 [1]. In addition, repeated supratherapeutic doses can cause hepatotoxicity in children with certain risk factors, including decreased oral intake [2-4].

The clinical manifestations and diagnosis of acetaminophen poisoning in children and adolescents will be presented here. Management of acetaminophen poisoning in children and adolescents and the evaluation and management of acetaminophen poisoning in adults is discussed separately. (See "Management of acetaminophen (paracetamol) poisoning in children and adolescents" and "Acetaminophen (paracetamol) poisoning in adults: Pathophysiology, presentation, and diagnosis" and "Acetaminophen (paracetamol) poisoning in adults: Treatment".)


Acetaminophen remains a major cause of overdose in children throughout the world. In the United States, pediatric acetaminophen exposures account for approximately 30,000 reports to the National Poison Data System annually [5]. The outcome of acetaminophen poisoning in children and adolescents is nearly always good if the antidote, N-acetylcysteine (NAC), is administered within 8 to 10 hours of ingestion. Mortality is rare in children and adolescents. (See "Management of acetaminophen (paracetamol) poisoning in children and adolescents", section on 'N-acetylcysteine'.)

Patterns of exposure — The potential for toxicity from acetaminophen overdose in children and adolescents largely depends upon the circumstances surrounding the exposure:

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Literature review current through: Dec 2017. | This topic last updated: Nov 22, 2016.
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