Seventy-six patients receiving cisplatin and noncisplatin-containing cancer chemotherapy were treated with an outpatient phase II metoclopramide regimen. The program consisted of an outpatient intravenous loading dose of metoclopramide before chemotherapy, followed by oral metoclopramide at 1, 3, 5, and 8 hours after chemotherapy. Three oral dose levels were evaluated. Treatment with 2 mg/kg/dose or 100 mg/dose resulted in no vomiting in 53% of 65 evaluable patients, and 0-2 episodes of emesis in 74%. Oral doses of 50 mg/dose were less effective, preventing emesis in 18%. This trial demonstrated the antiemetic effectiveness of high-dose oral metoclopramide in a new schedule designed for the outpatient setting. The side effects included restlessness (51% of patients), dystonic reactions (9%), and gastrointestinal complaints (41%).