Most risks depend on the particular patient, disease, and type of ERCP procedure and treatments. Complications generally occur in 5-20% of patients.
Pancreatitis is the most common side effect of an ERCP. It occurs in 10% of ERCPs and generally requires hospital admission and generally settles in one to three days in almost all cases. The treatment for mild pancreatitis usually consists of restriction of oral intake to ice chips, intravenous fluids and analgesics (pain medications) as needed. Severe pancreatic damage can result in the formation of pseudocyst or abcesses, which may require a prolonged hospital stay. This occurs in less than 1% of patients. It can occur even in the most expert hands.
Other important complications can occur after treatments such as sphincterotomy. A sphincterotomy can trigger bleeding, which can be controlled by the doctor during the ERCP. It is rare and uncommon for a blood transfusion to be needed. Sphincterotomy may result in a perforation when the cut extends into the tissues behind the duodenum and pancreas. Most perforations can be treated medically (with IV fluids, antibiotics, and nasogastric tube). In severe cases it may require surgery. On very rare occasions, the endoscope itself can cause a perforation (make a hole). This type of perforation usually requires surgical treatment.
Infection can occur in the bile ducts or pancreas after ERCP, especially when there is duct obstruction that cannot be treated by the ERCP procedure. Antibiotics will be required, and possibly another type of drainage procedure such as surgery.
The fluoroscope involves a small dose of radiation; this is no greater exposure than any other standard x-ray test and is well within the recommended limits. Possible drug reactions could occur with the medications and can cause nausea and skin reactions.
About 1% of ERCP procedures can result in severe complication. These types of complications would require a prolonged hospital stay, treatment in an intensive care unit, or surgery. Death rarely occurs.