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Acetaminophen (paracetamol) poisoning in adults: Treatment

Kennon Heard, MD
Richard Dart, MD, PhD
Section Editor
Stephen J Traub, MD
Deputy Editor
Jonathan Grayzel, MD, FAAEM


Acetaminophen (APAP) poisoning is among the most common causes of medication-related poisoning and death. Acetaminophen poisoning may occur following a single acute ingestion or through the repeated ingestion of supratherapeutic amounts. The management of the acetaminophen-poisoned patient may include stabilization, decontamination, and administration of N-acetylcysteine, a specific antidote. The duration of N-acetylcysteine treatment is determined by the type of ingestion and the presence or absence of elevated serum alanine aminotransferase (ALT) concentrations.

The treatment of APAP poisoning is reviewed here. The diagnosis of APAP poisoning, both acute and chronic, and the management of hepatic injury or failure are discussed separately. (See "Acetaminophen (paracetamol) poisoning in adults: Pathophysiology, presentation, and diagnosis" and "Acute liver failure in adults: Management and prognosis".)


The initial management of acetaminophen poisoning is determined by the patient's presenting symptoms. Most patients who present early (within 24 hours) after an acute acetaminophen ingestion are asymptomatic, while others may require treatment for symptoms related to coingestants.

As there are no early symptoms that predict acetaminophen toxicity, poisoning severity following an acute ingestion is quantified by plotting a timed serum acetaminophen concentration on the modified Rumack-Matthew nomogram (figure 1). Patients with serum acetaminophen concentrations that fall above the treatment line following an acute overdose are treated with N-acetylcysteine. In addition, N-acetylcysteine is given to all patients at significant risk for hepatotoxicity following an ingestion of acetaminophen. (See 'Antidote: acetylcysteine' below.)

Use of the nomogram, as well as risk factors for hepatotoxicity and the diagnosis of both acute and chronic acetaminophen poisoning, are discussed separately. A summary table to facilitate emergent management is provided (table 1). (See "Acetaminophen (paracetamol) poisoning in adults: Pathophysiology, presentation, and diagnosis".)

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Literature review current through: Nov 2017. | This topic last updated: Aug 21, 2017.
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