High doses of metoclopramide or droperidol in the prevention of cisplatin-induced emesis.

The antiemetic effects of the benzamide metoclopramide (MCL, Paspertin) and of the butyrophenone droperidol (DRO, Dehydrobenzperidol) were compared by two sequential analytical trials in cisplatin treated patients. In the first trial (cisplatin 60-90 mg/m2) the drugs were given as loading infusions (MCL 0.5 mg/kg, and DRO 0.05 mg/kg, each per b.w./h over 2 hr), beginning 2 hr before cisplatin administration; this was followed by the maintenance infusion at half the dose, over 24 hr (total dose of MCL 7 mg/kg, and DRO 0.7 mg/kg b.w. per cycle, resp.). During the second trial (cisplatin 90-120 mg/m2) the antiemetic dosages were doubled (total dose of 14 or 1.4 mg/kg per cycle. After 12 and 14 treatment pairs, resp., MCL was significantly (P less than 0.05) more effective than DRO. Clinically antiemetic protection (i.e. less than three vomiting episodes) were seen in 9 of 12 and 13 of 14 patients, resp., compared with only 5 of 12 and 5 of 14 patients on DRO. The incidence of major extrapyramidal side-effects was more than 2-fold higher at DRO. The benefit/risk relationships (i.e. the relation between the prevented emetic episodes and the number of extrapyramidal reactions seen) of MCL were 2.7-3.0-fold better than those of DRO. The relatively higher antiemetic efficacy of MCL may be due to its additional gastrointestinal mechanisms.