Table 3

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study weaknesses
Underhill TJ et al, 1990, UK¹	60 patients who had taken 5 g or more of paracetamol within 4 hours of attendance.	RCT	Plasma concentrations at 0, 60, 90 and 150 minutes post treatment	Activated charcoal group had significantly better fall in paracetamol concentration at 150 min	Small study
	Gastric lavage (14) v ipecacuana (21) v activated charcoal (20) v nothing (5)
Spilller HA et al, 1994, USA²	122 patients with paracetamol overdose within the previous 12 hours.	Observational study	Hepatotoxicity (defined as SGOT over 125 units/l)	Significantly less (5% v 20%) in groups receiving activated charcoal	Spectrum is of patients contacting a poisons centre. No power study.
	Activated charcoal (40) v activated charcoal and N acetylcysteine (57) v activated charcoal and high dose N acetyl cysteine (25)
Buckley NA et al, 1999, Australia³	981 consecutive paracetamol poisonings.	Observational study	Risk of “high risk” concentration	Significantly less change of toxic level if activated charcoal given (odds ratio 0.36 {0.23–0.58})
	Gastric lavage and charcoal v charcoal alone v nothing