In a pilot study we evaluated the efficacy and tolerability of a four-drug antiemetic combination (metoclopramide, dexamethasone, diphenhydramine and lorazepam) in cancer patients submitted to cisplatin chemotherapy at doses greater than or equal to 50 mg/m2. Fifty male patients entered the study. Complete protection from vomiting and nausea was obtained in 41 patients (82%) (95% confidence limits 71 and 93%). Toxicity was slight except for moderate sedation in 10% of patients necessitating their hospitalization. Only one extrapyramidal reaction (akathisia) was observed. When these results were compared to our previous experience in male patients treated with a combination of metoclopramide, dexamethasone and diphenhydramine without lorazepam, used at the same doses and schedule, no clear benefit and higher toxicity was observed.