Intravenous administration of ondansetron vs. metoclopramide for the prophylaxis of postoperative nausea and vomiting

: This randomized, double-blind, multicentre, parallel-group study compared the efficacy and safety of an intravenous dose of ondansetron 4 mg for the prevention of postoperative nausea and vomiting (PONV) with metoclopramide 10 mg and placebo in patients undergoing major gynaecological surgery. A total of 1044 patients (465 ondansetron, 462 metoclopramide, 117 placebo) received study medication immediately prior to induction of anaesthesia and were included in the analysis of data. The proportion of patients experiencing no emesis and no nausea or provided with rescue antiemetic medication, the number of emetic episodes, and the duration and severity of nausea were recorded during the 24-h period after recovery. Significantly more patients who received ondansetron had no emetic episodes (44%) than those who received metoclopramide (36%, P = 0.049) or placebo (25%, P < 0.001). A higher proportion of patients receiving ondansetron (32%) did not experience nausea (metoclopramide 24%, P = 0.009; placebo 16%, P < 0.001). Significantly fewer patients in the ondansetron group required rescue medication or were withdrawn due to treatment failure (P < 0.05). In the ondansetron group the total number of emetic episodes, the median time to the first emetic episode or treatment failure, and the duration and severity of nausea were reduced significantly compared with metoclopramide or placebo (P < 0.05). The safety profile was similar for each treatment group.