All of the endoscopic and clinical practices will follow the current standard of care of the Yale interventional endoscopy department. Participation in the study will not alter this in any way. The experimental intervention is limited to the administration of a single dose of indomethacin, injected into the endoscope channel prior to removal of the scope at the conclusion of the ERCP and subsequent monitoring for signs and symptoms of post-ERCP pancreatitis, much of which is also part of routine clinical practice.