The prevention of postoperative nausea and vomiting using a combination of ondansetron and droperidol

We have studied the effect of combination antiemetic therapy (ondansetron and droperidol) with morphine delivered by patient-controlled analgesia following major gynaecological surgery. Sixty patients were randomly allocated to one of three treatment regimens; ondansetron alone (4 mg bolus and 0.13 mg.ml-1 in the morphine solution), droperidol alone (1.25 mg bolus and 0.05 mg.ml-1 in the morphine solution), or both drugs in combination. For the first 12 postoperative hours, patients receiving combination therapy experienced significantly less nausea than those receiving single antiemetic therapy (p < 0.001). There was no difference between the regimens from 12 to 18 h. We conclude that a combination of ondansetron and droperidol added to morphine in a patient-controlled analgesia system reduces postoperative nausea to a greater extent than treatment with either drug alone following major gynaecological surgery.