Best Evidence Topics
  • Send this BET as an Email
  • Make a Comment on this BET

Activated charcoal is indicated in paracetamol overdose

Three Part Question

In [patients poisoned with paracetamol] does [activated charcoal alone or in combination with other treatments] reduce [hepatotoxicity]?

Clinical Scenario

A 23 year old woman attends the Emergency Department having taken 60 500mg paracetamol tablets 2 hours prior to presentation. You wonder whether she should receive activvated charcoal.

Search Strategy

Medline 1966-03/00 using the OVID interface.
[({ OR} AND {exp poisoning OR OR exp overdose OR}) AND {exp charcoal OR} LIMIT to human AND english.

Search Outcome

71 papers found of which 68 were irrelevant or of insufficient quality. The remaining 3 papers are shown in the table.

Relevant Paper(s)

Author, date and country Patient group Study type (level of evidence) Outcomes Key results Study Weaknesses
Underhill TJ et al,
60 patients who had taken 5 gm or more of paracetamol within 4 hours of attendance. Gastric lavage (14) vs ipecacuana (21) vs activated charcoal (20) vs nothing (5)RCTPlasma concentrations at 0, 60, 90 and 150 minutes post treatmentActivated charcoal group had significantly better fall in paracetamol concentration at 150 minSmall study
Spiller HA et al,
122 patients with paracetamol overdose within the previous 12 hours. Activated charcoal (40) vs activated charcoal and N acetylcysteine (57) vs activated charcoal and high dose N acetyl cysteine (25)Observational studyHepatotocxicity (defined as SGOT over 125 units/l)Significantly less (5% vs 20%) in groups receiving activated charcoalSpectrum is of patients contacting a poisons centre. No power study.
Buckley NA et al,
981 consecutive paracetamol poisonings. Gastric lavage and charcoal vs charcoal alone vs nothingObservational studyRisk of "high risk" concentrartionSignificantly less change of toxic level if activated charcoal given (Odds Ratio 0.36 {0.23 - 0.58})


There are no high quality studies in this area. In particular there is no data to indicate how long after poisoning activated charcoal remains effective.

Clinical Bottom Line

Activated charcoal should be given to all patients with significant paracetamol poisoning who present acutely.


  1. Underhill TJ, Greene MK, Dove AF. A comparison of the efficacy of gastric lavage, ipecacuanha and activated charcoal in the emergency management of paracetamol overdose. Arch Emerg Med 1990;7(3):148-54.
  2. Spiller HA, Krenzelok EP, Grande GA et al. A prospective evaluation of the effect of activated charcoal before oral N acetylcysteine in acetaminophen overdose. Ann Emerg Med 1994;23(3):519-23.
  3. Buckley NA, Whyte IM, O'Connell DL et al. Activated charcoal reduces the need for N-acetylcysteine treatment after acetaminophen (paracetamol) overdose. J Toxicol - Clin Toxicol 1999;37(6):753-7.