The paper examines the role of ranitidine in the prevention of postoperative hyperamylasemia, a complication following major biliary tract surgery, especially if associated with intraoperative cholangiography. Forty patients underwent cholecystectomy and intraoperative cholangiography: calculosis of the choledochus was observed in 11 patients and a revision of the VBP was therefore carried out involving the transcystic insertion of Kehr's tube. Patients were randomly subdivided into two groups: group A (treated with 50 mg ranitidine 4 times a day e.v.) and group B (no anti H2 treatment). No significant differences were noted between the two groups with regard to the onset of hyperamylasemia, although it is worth reporting that ranitidine virtually eliminated all hemorrhagic complications due to ulcer or postoperative gastritis.