Study of the prophylactic effect of droperidol, alizapride, propofol and promethazine on spinal morphine-induced pruritus

We have compared the use of alizapride, propofol, droperidol and promethazine for the prevention of spinal morphine-induced pruritus. Three hundred ASA I or II women undergoing Caesarean section under spinal anaesthesia, in which morphine 0.2 mg was added to a local anaesthetic, were assigned randomly to receive i.v., in the operating room, just after delivery of the baby, alizapride 100 mg, propofol 20 mg, droperidol 1.25 mg, promethazine 50 mg or saline 2 ml (control group). In the postoperative period, the women were assessed for pruritus (absent, mild, moderate or severe) or other untoward symptoms by blinded observers. We used 95% confidence limits (95% CI) for the cumulative incidence of moderate and severe pruritus to compare the groups, and the NNT and 95% CI to compare droperidol, propofol and alizapride as for their effectiveness in preventing pruritus. For other untoward effects, the χ2-test was used, results being considered significant when P