Patients scheduled to undergo diagnostic or therapeutic ERCP would be serially enrolled. Standard indications for ERCP will include the following: evaluation of obstructive jaundice, unexplained pancreatitis, recurrent pancreaticobiliary pain and abnormal liver tests. Those patients who are deemed to be at increased risk of pancreatitis (suspected sphincter of oddi dysfunction, age < 40 yrs, normal bilirubin, prior post ERCP pancreatitis, difficult cannulation, pancreatic duct injection, pancreatic duct sphincterotomy, undergoing pre-cut sphincterotomy and balloon dilation of the biliary sphincter) would undergo placement of a 3 French pancreatic stent at the time of ERCP. Prospective randomized studies have demonstrated a marked decrease in post-ERCP pancreatitis rates in high risk patients who have undergone pancreatic stenting. Following ERCP and therapy (if required), they would be randomized to receive a dose of indomethacin or placebo instilled into the duodenum via the biopsy channel of the duodenoscope. Patients as well as physicians and nurses performing the procedure and overseeing the study will be unaware of treatment assignments.