The procedure takes place at a hospital, surgery center or clinic. You usually are told to fast for about 8 hours beforehand, and you should avoid smoking and taking certain medications. You might be given antibiotic medication before the procedure to prevent infection. You will receive sedation for the procedure.
Your throat is numbed with a local anesthetic, and then a thin, flexible tube (endoscope) is inserted into your mouth, down your throat and esophagus and into your stomach and small intestine to visualize your bile duct. The tube is equipped with a tiny camera that transmits pictures that your doctor sees on a monitor. A small tube is placed in a bile duct near the sphincter of Oddi to measure how it is contracting and expanding. If a problem is found, your doctor might be able to treat it immediately.