In a double-blind randomized trial, we compared the efficacy and tolerability of high-dose (2 mg/kg X 4) intravenous metoclopramide (MTC) versus metoclopramide plus high-dose (250 mg X 2) intravenous methylprednisolone (MP) administered for the first 2 days in untreated patients submitted to dacarbazine chemotherapy for 5 days. Thirty-four patients entered the study. Complete protection from nausea and vomiting was achieved in the majority of patients all through the study period with both antiemetic treatments, with slightly greater efficacy at day 2 for the combination. However, after suspension of the antiemetic therapy, there was a relapse of vomiting in patients. Side effects were not different between the two treatments, but extrapyramidal reactions were significantly increased on the second day of antiemetic therapy. In conclusion, high-dose MTC with or without MP can give good antiemetic protection and the combination seems to be slightly more efficacious. However, the relapse of vomiting after discontinuing antiemetic treatment and the high incidence of extrapyramidal reactions justify further studies to find a better antiemetic treatment.