[Optimal timing of granisetron administration for the prevention of carboplatin-induced acute emesis].

This prospective pilot study was undertaken to determine whether delayed administration of one of the serotonin-receptor antagonists (granisetron) reduced carboplatin--induced emesis. The subjects were patients who were scheduled to undergo at least three courses of carboplatin based chemotherapy, in whom acute emesis occurred at the first course. Granisetron was administered therapeutically for the first course. Conventional prophylactic granisetron was given 30 min before carboplatin administration for the second course. For the third course, granisetron was administered 5 hr after completion of carboplatin administration. The degrees of appetite loss, nausea and frequency of vomiting on the Day 1 were compared between the three courses. Thirteen patients were evaluated. Acute emesis occurred 8 +/- hr after completion of carboplatin administration in the first courses of these patients. The degree of nausea and frequency of vomiting were reduced by administrating the granisetron five hours after carboplatin when compared with therapeutic granisetron administration or administration 30 min before carboplatin. The degree of appetite loss was significantly lowered by administering the granisetron 5 hr after carboplatin administration. Administration of granisetron 5 hr after carboplatin may thus lessen carboplatin-induced emesis more than conventional granisetron administration. A large-scale comparative study is warranted.