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BACKGROUND: Poisoning withparacetamol (acetaminophen) is a common cause of hepatotoxicity in the WesternWorld. Inhibition of absorption, removal from the vascular system, antidotes,and liver transplantation are interventions for paracetamol poisoning.OBJECTIVES: To assess the benefits and harms of interventions for paracetamoloverdose. SEARCH STRATEGY: We identified trials through electronic databases,manual searches of bibliographies and journals, authors of trials, andpharmaceutical companies until December 2005. SELECTION CRITERIA: Randomisedclinical trials and observational studies were included. DATA COLLECTION ANDANALYSIS: The primary outcome measure was all-cause mortality plus livertransplantation. Secondary outcome measures were clinical symptoms, (eg,hepatic encephalopathy, fulminant hepatic failure), hepatotoxicity, adverseevents, and plasma paracetamol concentration. We used Peto odds ratios and oddsratios with 95% confidence intervals (CI) for analysis of outcomes. Random- andfixed-effects meta-analyses were performed. MAIN RESULTS: Ten small andlow-methodological quality randomised trials, one quasi-randomised study, and48 observational studies were identified. It was not possible to performrelevant meta-analyses of randomised trials that have addressed our outcomemeasures. Activated charcoal, gastric lavage, and ipecacuanha are able toreduce the absorption of paracetamol, but the clinical benefit is unclear. Ofthese, activated charcoal seems to have the best risk-benefit ratio. N-acetylcysteineseems preferable to placebo/supportive treatment, dimercaprol, and cysteamine,but N-acetylcysteine's superiority to methionine is unproven. It is not clearwhich N-acetylcysteine treatment protocol offers the best efficacy. No strongevidence supports other interventions for paracetamol overdose.N-acetylcysteine may reduce mortality in patients with fulminant hepaticfailure (Peto OR 0.26, 95% CI 0.09 to 0.94, one trial). Liver transplantationhas the potential to be life saving in fulminant hepatic failure, butrefinement of selection criteria for transplantation and long-term outcomereporting are required. AUTHORS' CONCLUSIONS: Our results highlight a paucityof randomised trials on interventions for paracetamol overdose. Activatedcharcoal seems the best choice to reduce absorption. N-acetylcysteine should begiven to patients with overdose but the selection criteria are not clear. NoN-acetylcysteine regime has been shown to be more effective than any other. Itis a delicate balance when to proceed to liver transplantation, which may belife-saving for patients with poor prognosis.Leggil'articolo: è full text!