Most children vomit after strabismus surgery. Administration of intravenous droperidol to unpremedicated paediatric patients following induction but prior to eye manipulation markedly reduces the incidence of postoperative emesis. This study tested the hypothesis that even earlier administration of droperidol, orally as a component of an oral premedication, would further reduce the incidence of postoperative emesis in this group of patients. Sixty-five patients were randomized into three premedication groups. One group received the standard oral premedication used for all outpatients at our institution (meperidine 1.5 mg.kg-1, diazepam 0.15 mg.kg-1, atropine 0.02 mg.kg-1). In the other two groups, droperidol in a dose of 50 or 75 micrograms.kg-1 was substituted for the diazepam. Droperidol-treated groups demonstrated a significantly lower incidence of vomiting prior to hospital discharge compared to the groups that received the standard oral premedication (standard--73 per cent, 50 micrograms.kg-1 droperidol--33 per cent, 75 micrograms.kg-1 droperidol--36 per cent) without prolonging hospital stay.