A randomized, double-blind controlled trial of nabilone versus chlorpromazine was performed in 20 patients with advanced gynaecological cancer who received chemotherapy including cis-platinum. Each patient served as his own control. Nabilone was administered at a dose of 3 mg given orally three times a day, starting the day before cis-platinum and ending the day after. Chlorpromazine was administered at a dose of 12.5 mg given IM, 15 minutes before the start of cis-platinum. Nabilone, in comparison with chlorpromazine did not significantly reduce the number of vomiting. Ten patients preferred nabilone, 5 preferred chlorpromazine and 3 were undecided. Predominant side effects noted by patients were similar for both agents and included somnolence, dry mouth and orthostatic hypotension. No other intervention besides reassurance of the patient was necessary to treat these adverse reactions.