Management overview for immediate-release paracetamol poisoning

For paracetamol poisoning presenting in primary care, see Paracetamol poisoning: advice for primary care providers.

This monograph discusses management of acute ingestions of immediate-release paracetamol as a solid preparation, and as a liquid formulation in patients older than 6 years. It does not cover the management of an unintentional overdose of intravenous paracetamol—seek advice from a poisons information centre. Other scenarios covered in different monographs include:

Paracetamol is widely available and responsible for a large proportion of accidental and deliberate cases of poisoning. Paracetamol poisoning is common, but rarely causes severe liver injury or death. Children younger than 6 years are less susceptible to paracetamol toxicity (see Paracetamol poisoning: liquid formulations in a child younger than 6 years).

If a patient has taken a mixture of immediate-release and modified-release paracetamol tablets, treat as for poisoning caused by modified-release paracetamol.

Note: Treat patients who have taken a mixture of immediate-release and modified-release paracetamol as for poisoning caused by modified-release paracetamol.

Refer patients with suspected deliberate paracetamol poisoning to hospital for assessment, regardless of the dose ingested. The hospital must be able to measure liver biochemistry and serum paracetamol concentration urgently. For advice on the management of acute paracetamol poisoning presenting to rural and remote facilities lacking pathology services, refer to the 2019 Australian and New Zealand guidelines for the management of paracetamol poisoning1.

Treatment for immediate-release paracetamol poisoning may involve gastrointestinal decontamination with activated charcoal, and the antidote, acetylcysteine2. Acetylcysteine given within 8 hours of paracetamol ingestion prevents hepatotoxicity3 in most cases. Indications for acetylcysteine therapy depends on the time since ingestion, the serum paracetamol concentration, and the serum ALT concentration (in some situations).

If the serum paracetamol and ALT concentrations will not be available within 8 hours of ingestion, start treatment with acetylcysteine immediately.

1 Chiew AL, Reith D, Pomerleau A, Wong A, Isoardi KZ, Soderstrom J, et al. Updated guidelines for the management of paracetamol poisoning in Australia and New Zealand. Med J Aust 2019.  [URL] Return
2 Acetylcysteine is also commonly known as N-acetylcysteine, and the abbreviation ‘NAC’ is used in many texts and local protocols.Return
3 Hepatotoxicity is defined as serum alanine aminotransferase (ALT) concentration (or aspartate aminotransferase [AST]) of 1000 U/L or higher.Return