Postoperative nausea and vomiting after craniotomy may increase intracranial pressure and morbidity in children. This prospective, randomized, placebo-controlled and double-blinded study was designed to evaluate the antiemetic efficacy of prophylactic ondansetron after intracranial tumour resections in children.

Ninety children were divided into three groups and received saline (Group 1), ondansetron 150 μg kg−1 intravenously at dural closure (Group 2) or two doses of ondansetron 150 μg kg−1 intravenously, the second dose repeated after 6 h (Group 3). Episodes of nausea, emesis and side-effects were noted for 24 h postoperatively.

Overall 24 h incidence of postoperative nausea and vomiting was not significantly different among the three groups (9 (37.5%) in Group 1 vs. 7 (27%) in Group 2 and 8 (32%) in Group 3, P = 0.73). No difference in rescue antiemetic treatment or postoperative nausea and vomiting at specific time intervals (0–6 and 6–24 h postoperative period) was seen among the three groups. No significant side-effects were noted in any of the three groups.

Ondansetron, in this study of 90 children, was not very effective in preventing nausea and vomiting after neurosurgical operations.