prospective, randomized, double-blind, comparative study of the efficacy of intravenous ondansetron and palonosetron for prevention of postoperative nausea and vomiting

Palonosetron is a second generation 5-Hydroxytryptamine-3 receptor antagonist with longer half life and higher receptor binding affinity than Ondansetron. To assess the efficacy and safety profile of intravenous palonosetron compared to the ondansetron for prevention of post-operative nausea and vomiting [PONV] under general anesthesia. A prospective, randomized, placebo-controlled, double-blind study was conducted in 90 patients aged 20-60 years, undergoing major surgeries. Group I [n=30] received placebo injection; Group II [n=30] received inj. ondansetron 8 mg and Group III [n=30] received inj. palonosetron 0.075 mg IV. In the operating room, the study drugs were given IV in equal volume of 4ml, before inducing the patients. In postoperative period each patient was observed for retching, nausea and/or vomiting at 30 min; and then at 1, 2, 6, 12 and 24 hours. Any side effects intra-operatively and post-operatively were recorded. The number of patients, who remained vomiting free in the first 24 hours after surgery was 56.6%, 80% and 86% in the placebo, Ondansetron and Palonosetron groups respectively. The difference with placebo was highly significant for ondansetron [p < 0.05], and highly significant for palonosetron [p=0.009]. The difference in vomiting between Ondansetron and Palaonosetron was not significant but the incidence of nausea was significantly less common in the Palonosetron group than the Ondansetron group [16.7% vs. 43.4%, p=0.006]. We conclude that the second generation 5-HT3 antagonist, palonosetron is significantly more effective against PONV than ondansetron. It has a particularly more pronounced and prolonged effect on postoperative nausea