Patients undergoing laparoscopic gynecological surgery have a remarkably high incidence of postoperative nausea and vomiting (PONV). The purpose of this study was to evaluate the effect of the timing of ramosetron administration on its antiemetic efficacy in patients undergoing laparoscopic gynecological surgery.

One hundred and twenty patients undergoing laparoscopic gynecological surgery under general anesthesia were randomized to receive 0.3 mg of ramosetron intravenously either immediately after induction (group I, n = 60) or at the completion of surgery (group II, n = 60). Occurrences of nausea and vomiting, the need for rescue antiemetics and analgesics, pain score, as well as adverse events associated with study medications, were recorded for 48 hrs after the operation.

The incidence of postoperative nausea and vomiting in the I and II groups were 46.7%, 41.7% respectively. There was no significant difference between the groups in the incidences of PONV, the need for rescue antiemetics and analgesics, pain score and adverse events associated with study medications (P > 0.05).

The effect of ramosetron administered either immediately after induction or at the completion of surgery was similar to each other on its efficacy as a prophylactic antiemetic in patients undergoing laparoscopic gynecological surgery.