ABSTRACT
BACKGROUND: Nausea and emesis are undesirable events that may cause discomfort and suffering in the postoperative period. This study was carried out to evaluate the efficacy and safety of ondansetron for preventing postoperative nausea and vomiting in patients undergoing gastrointestinal tract surgery. METHODS: Using a randomized double-blind study design, 408 surgical patients (163 male and 245 female) receiving general endotracheal anesthesia were studied at five medical centers in Bangkok. Ondansetron (4 mg) or placebo was administered prior to induction of anesthesia. Episodes of nausea and vomiting, adverse events and laboratory tests (complete blood count and liver function test) were evaluated during 24 hours after study drug administration. RESULTS: The incidence of postoperative nausea and vomiting in the placebo group (42.7 and 35.2%) were significantly higher than the ondansetron group (23.9 and 15.4%). However, no significant differences occurred in the incidence of adverse events or changes in laboratory tests in the ondansetron group compared to the placebo group. CONCLUSIONS: Ondansetron 4 mg given intravenously before surgery is safe and effective for preventing postoperative nausea and emesis following gastrointestinal tract surgery.