Prochlorperazine and transdermal scopolamine added to a metoclopramide antiemetic regimen. A controlled comparison. Cisplatin-induced nausea and vomiting occurs both acutely and over a prolonged period of time. These symptoms may be incapacitating and are frequently given as a reason to discontinue therapy. We compared prochlorperazine and transdermal scopolamine when added to a standardized metoclopramide antiemetic regimen. Twenty-seven patients receiving cisplatin at 100 mg/m2 were randomly assigned to one of the two treatment arms. Patients were observed during chemotherapy and answered a standard questionnaire 24-26 hours later. Among similar treatment groups no differences were seen regarding the number of emetic events, level of nausea, degree of sedation or overall acceptability of one treatment arm or another. While not superior to prochlorperazine, transdermal scopolamine is a useful antiemetic agent and can be combined with metoclopramide in an attempt to reduce cisplatin-induced nausea and vomiting. Further evaluation of this approach is needed. 