Epidural ondansetron is more effective to prevent postoperative pruritus and nausea than intravenous ondansetron in elective cesarean delivery

Background. Postoperative pruritus, nausea, and vomiting are common side effects of intrathecal or epidural opioids. Intravenous ondansetron has been used for postoperative emesis. However, there are no reports regarding epidural ondansetron. Two studies were conducted to evaluate the prophylactic effects of epidural ondansetron for opioid-induced pruritus, nausea, and vomiting. Methods. Neurotoxic signs were checked after epidural injection of ondansetron in rats. A clinical study was conducted to compare the prophylactic effects of epidural ondansetron with intravenous ondansetron for opioid-induced pruritus, nausea, and vomiting in cesarean delivery. Results. No neurotoxic evidence was found in rats. The incidence of pruritus and nausea was significantly lower in the epidural ondansetron group than in the intravenous ondansetron group at 24 and 48 h postoperatively. Conclusions. Epidural ondansetron is more effective in preventing postoperative pruritus and nausea than intravenous ondansetron.