Observation and patient disposition after immediate-release paracetamol poisoning

Patients who present within 8 hours of an acute ingestion of immediate-release paracetamol do not need to be admitted if their initial serum paracetamol concentration is below the treatment nomogram line. Advise them to return to hospital if they develop symptoms of acute liver injury, such as abdominal pain, nausea or vomiting.

All patients with deliberate self-poisoning require psychiatric assessment before discharge. To facilitate psychiatric assessment and treatment, if indicated, patients may require a longer period of observation.

Admit patients who are treated with acetylcysteine to hospital.

In patients who were started on acetylcysteine therapy without an initial serum paracetamol concentration, stop the infusion and discharge them when their:

• serum paracetamol concentration is below the treatment nomogram line and serum ALT concentration is lower than 50 U/L—for those presenting 8 to 24 hours since ingestion
• serum paracetamol concentration is lower than 10 mg/L (66 micromol/L) and serum ALT concentration is lower than 50 U/L—for those presenting more than 24 hours since ingestion.

Patients who complete the 20-hour acetylcysteine regimen 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.