ObjectiveTo test the hypothesis that administration of activated charcoal is as efficacious and safe as the combination regimen of gastric emptying plus charcoal in adults after acute oral overdose.DesignProspective randomised controlled trial, with subjects presenting on odd‐numbered dates allocated to the emptied group (E), and those on even‐numbered dates to the not‐emptied group (NE).SettingPrincess Alexandra Hospital, Brisbane (a tertiary referral hospital), which serves an adult urban community, between 4 January 1988 and 11 June 1990.SubjectsConsecutive patients (13 years or older) who presented to the Emergency Department after ingesting an overdose of one or more compounds able to be adsorbed by activated charcoal.InterventionsAll patients received charcoal by the oral or nasogastric route. Those in the E group also had gastric emptying by ipecac‐induced emesis or gastric lavage.Outcome measuresClinical course during the first six hours after treatment began, length of hospital stay, complications.Results876 patients were eligible for the study. There were no significant differences between the E and NE groups in age and sex distribution, severity of the overdose or other characteristics, except the mean interval between presentation and administration of charcoal (91 min [SD, 52] for E group and 55 [SD, 41]for NE group;P= 0.0001). There were no significant differences between the E and NE groups in outcome, even when the groups were stratified for severity of the overdose or into subgroups that presented sooner or later than one hour after ingestion.ConclusionsGastric emptying can be omitted from the treatment protocol for adults after acute oral overdose.