Alizapride is a potent antiemetic, acting as a dopamine receptor antagonist on the chemoreceptor trigger zone with few gastrokinetic properties. Little is known of its activity on the human sphincter of Oddi (SO). The aim of this study was to assess the effect of alizapride on SO motor function and to evaluate a possible use of alizapride in premedication for endoscopy of the upper digestive tract. We selected ten patients who underwent retrograde cholangiopancreaticography, but had no evidence of biliary or pancreatic disease. Endoscopic manometry was applied before and for 10 min after administration of alizapride 100 mg i.v. No significant modification of basal pressure or phasic activity was observed. Alizapride can be proposed as an antiemetic in patients with biliary disorders.