Sulpiride, which has been utilized as an antipeptic ulcer and antidepressant in Japan, is one of the dopamine antagonists, and is considered to have anti vomiting activity. We designed a comparative controlled study of Sulpiride and Domperidone, against nausea and vomiting during cancer chemotherapy. A total of 69 cases were entered into this study, 34 cases being treated with Sulpiride at a dose of 100 mg i.v. or i.m. (S group), and 35 cases being treated with Domperidone at a dose of 10 mg i.v. (D group), before and after chemotherapy. Three cases from the S group and 4 cases from the D group were excluded from this study because of differences in the administration schedule. There was no difference in patient characteristics between the two groups, such as age, sex, original disease and antitumor agents. According to our criteria 27 of 31 cases in the S group showed effectiveness of the agent against nausea and vomiting (87%), while in the D group, 24 cases showed effectiveness (77%). There was no statistical difference between them, and no side effects were found in either group.