Effect of nabilone on nausea and vomiting after total abdominal hysterectomy.

In a prospective, double-blind study, we have examined the effect of preoperative nabilone on postoperative nausea and vomiting (PONV). Sixty women, less than 70 yr old, undergoing total abdominal hysterectomy, were allocated randomly to receive either nabilone 2 mg or metoclopramide 10 mg orally 90 min before induction of anaesthesia. The study was designed to detect a 50% difference in the incidence of postoperative vomiting between the two groups, with an 80% power of achieving a statistically significant result at the 5% level. Data from 53 patients were analysed: the incidences of nausea and vomiting for the metoclopramide group were 70% and 67%, respectively; the corresponding values for the nabilone group were 73% and 54%. These differences were not significant.