Double-blind comparison of alizapride, droperidol and ondansetron in the treatment of post-operative nausea

To compare the efficacy in the treatment of postoperative nausea and/or vomiting (PONV), 75 patients undergoing gynaecological procedures under general anaesthesia using N2O/enflurane who suffered from PONV in the first hour after surgery were randomly allocated to three groups containing 25 patients each to receive either alizapride 100 mg, droperidol 1 mg or ondansetron 8 mg (i.v.). Patients expressed the severity of their nausea on a Visual Analogue Scale (VAS) ranging from 0 (none) to 10 (as bad as possible). Vomiting was recorded as present or absent, and the number of emetic events was noted. Data were recorded until rescue medication was given or until 4 h after the administration of the study drug. There were no significant differences between the three groups in the average VAS scores and the presence of vomiting at the time of entry into the study. Fifteen and 30 min after the administration of the study drug, VAS decreased notably in all groups. This decrease was similar and statistically significant within each group. However, comparison between the three groups showed no statistically significant differences. There was no statistically significant difference between the three groups in the number of patients receiving rescue medication, the number of emetic events and the time from administration of the study drug until rescue medication was given. It is concluded that alizapride 100 mg, droperidol 1 mg and ondansetron 8 mg intravenously are equally effective in the treatment of PONV after gynaecological procedures and that the newer drugs alizapride and ondansetron offer no advantage over droperidol.