Observation and patient disposition after unintentional paracetamol poisoning

Advise patients who have taken supratherapeutic doses of paracetamol about safe paracetamol dosage.

Patients do not need to be admitted if their initial serum paracetamol concentration is lower than 20 mg/L (132 micromol/L) and the serum ALT concentration is lower than 50 U/L. Advise them to return to hospital if they develop symptoms of acute liver injury, such as abdominal pain, nausea or vomiting.

Admit patients who are treated with acetylcysteine to hospital.

Patients can be discharged when the:

  • serum ALT concentration is lower than 50 U/L, or falling if the baseline concentration was higher than 50 U/L1
  • serum paracetamol concentration is lower than 10 mg/L (66 micromol/L).

If the patient is being treated with extended therapy, stop acetylcysteine therapy and discharge when the:

  • serum ALT concentration is decreasing
  • INR is lower than 2.0
  • serum paracetamol concentration is lower than 10 mg/L (66 micromol/L)
  • patient is clinically well.

If the serum ALT concentration is higher than 50 U/L despite treatment, but is not rapidly rising, investigate for other causes of hepatotoxicity.

1 Patients with significant acute liver injury have a high or rapidly rising serum ALT concentration. Small fluctuations in ALT (eg 20 U/L or 10%) are common and do not on their own indicate the need for ongoing acetylcysteine therapy.Return