This study was designed to compare the antiemetic effect of betamethasone alone with that of betamethasone combined with metoclopramide. Forty-seven patients on chemotherapeutic regimens including cisplatin were entered into this study. Betamethasone was given in 4 doses of 20 mg/body at 30 minutes before and at 2.5 and 8 hours after cisplatin. Metoclopramide was given in 4 doses of 1mg/kg on the same schedule. Within 24 hours after the administration of cisplatin, no vomiting was observed in 42.9% of the patients treated with betamethasone alone and in 76.9% with betamethasone and metoclopramide. Betamethasone combined with metoclopramide was superior to betamethasone alone for the antiemetic effect in cisplatin-treated patients.