Patients who were discharged after an uneventful ERCP were contacted by telephone within 5 days to capture delayed occurrence of the primary end point. Patient demographics, risk factors, ERCP procedural elements, and follow-up data were recorded on standardized data-collection forms by an investigator or coordinator who was unaware of study-group assignments. The intramuscular route was selected on the basis of available small sized data suggesting that intramuscular NSAIDs are effective in preventing post-ERCP pancreatitis, perhaps owing to more rapid and complete bioavailability than with oral administration. (1) At the end of each procedure, the researchers recorded the details of the maneuvers performed, including the total time of the procedure, the number of attempts at cannulation, the number of pancreatic duct cannulations, the final diagnosis, and whether a sphincterotomy, a needle-knife papillotomy, or stent placement were performed. We did not use pancreatic duct stenting for prevention of pancreatitis. Patients were sedated with IV midazolam and IV continuous infusion of propofol under monitoring by anesthesiologist during whole time of procedure. Xylocaine spray was used as a local anesthetic. Serum amylase was determined 4 hours after ERCP.