Single-dose i.v. granisetron in the prevention of postoperative nausea and vomiting

In this randomized, double-blind, parallel group, placebo-controlled, dose-ranging study, we have compared three doses (0.1 mg, 1.0 mg and 3.0 mg) of the 5-HT3 receptor antagonist, granisetron (Kytril), as prophylactic therapy for the prevention of postoperative nausea and vomiting. The aims were to determine the optimal dose of granisetron and to evaluate its safety profile. We studied 527 adult patients, undergoing elective open abdominal surgery or vaginal hysterectomy during general anaesthesia. Antiemetic prophylaxis with a single dose of granisetron 1.0 mg or 3.0 mg resulted in a significant reduction (P < 0.001 compared with placebo) in the numbers of patients experiencing postoperative vomiting, or nausea, or who achieved total control during the postoperative periods 0-6 h and 0-24 h. The two higher doses of granisetron (1.0 mg and 3.0 mg) provided effective prophylaxis against vomiting, with 78% and 77% of patients, respectively, being free from vomiting in the first 6 h after surgery, and 63% and 62% in the first 24 h. This compares with 50% and 34% at 0-6 h and 0-24 h, respectively, in the placebo group. Granisetron was well tolerated and the optimum dose was 1.0 mg.