ERCP test

ERCP stands for endoscopic retrograde cholangio pancreatography. This test can help to diagnose conditions of the liver, bile ducts, pancreas or gallbladder.

What is an ERCP?

Your doctor puts a tube called an endoscope down your throat to take x-rays of the pancreas, gallbladder and bile ducts. The endoscope is a long flexible tube with a small camera and light at the end.

The doctor can look down the endoscope or at pictures on a TV monitor. The test takes between 30 minutes and 2 hours.

Diagram of an endoscopic retrograde cholangio pancreatography

Why you might have it

Your doctor might use an endoscopic retrograde cholangio pancreatography (ERCP) to check whether there is a growth or any abnormal looking area in your gallbladder. They can also look at the inside of your small bowel (duodenum) and take tissue samples (biopsies).

This test can also show a narrowing or blockage of the bile duct or pancreatic duct. So it can also help with planning surgery.

Preparing for an ERCP

Before the ERCP, you usually have a blood test to check how well your blood clots.

Let the hospital department where you are having the test know if you're taking medicine that changes how your blood clots. This includes:

  • aspirin
  • clopidogrel
  • arthritis medicines
  • warfarin or heparin
  • apixaban or rivaroxaban

You might need to stop taking this type of medicine a number of days before the ERCP. Your doctor or nurse will tell you when you should stop. They will also tell you if you need to stop taking any other medicines and when.

You can't eat for 6 to 8 hours before the test. This is so that your stomach and duodenum are empty. You might be able to drink sips of water up to 2 hours before your appointment. Your doctor or nurse gives you written instructions about this beforehand.

Talk to your doctor or nurse if not eating could be a problem for you. For example, if you have diabetes.

Because you have sedation for the test to make you drowsy, you will need someone with you to take you home and stay overnight. You shouldn’t drive, drink alcohol, operate heavy machinery or sign any legally binding documents for 24 hours.

It’s also a good idea to bring an overnight bag just in case you need to stay in hospital overnight.

How you have an ERCP

Just before the test

Your appointment letter tells you where to go. You usually go to the endoscopy department to have this test but you might have it in the x-ray department.

Before the procedure you see the doctor. They explain the procedure to you and ask you to sign a consent form. This is a good time to ask any questions you may have. 

You usually change into a hospital gown and remove any jewellery or metal objects on your body. As this will interfere with the x-ray pictures they take.  

You lie on the bed or x-ray couch. The nurse puts a small plastic tube (cannula) into the back of one of your hands. You may have antibiotics to prevent infection and fluids through a drip.

Your nurse gives you a plastic mouth guard to wear. This is to protect your teeth and gums during the test. They also give you oxygen through a tube that fits into your nose (nasal cannula).

During the test

You usually have an injection of sedation first to make you very drowsy. Your doctor might spray the back of your throat with a local anaesthetic to make it easier to swallow the endoscopy tube.

Once the sedative has worked, your doctor passes the endoscope tube through your mouth, down your throat into your stomach. They'll ask you to swallow as the tube goes down. You will be able to breathe normally, but you may gag slightly.

Once in the stomach, it then goes into your duodenum. This is where the pancreatic and bile ducts join. They might put a small amount of air into your stomach to help them see more clearly. This can make some people feel uncomfortable and like you want to burp.

They pass a thinner tube down through the endoscope which can fit into your bile duct. They then inject dye (contrast medium) through the tubes into the channels (ducts) of the biliary tree and pancreas so they can see them on x-ray pictures.

Your doctor can take samples of cells from the bile ducts using a brush (brush cytology). And they may also take pieces of tissue (biopsies). They send these samples to the laboratory for examination under a microscope. They may also take some photographs.

Your nurse checks your heart rate, breathing rate and oxygen levels throughout the test.

Detailed diagram of an endoscopic retrograde cholangic pancreatography (ERCP)

After the test

Your doctor removes the tube. You then need to rest for a while. You might need to stay in the department for a few hours.

You might not remember much (if anything) about the test when you wake up from the sedation.

After the test you might:

  • have a sore throat for a few days
  • have bloating and discomfort in your tummy (abdomen) for a day or two
  • feel sick or be sick after the sedation

Your nurse removes the cannula from your hand before you leave. You should be able to go home the same day. You won't be able to drive for the rest of the day and should have someone to go home with you and stay overnight.

Possible risks

There are possible risks with an ERCP and cholangioscopy. Some can be serious and life threatening. Your doctor makes sure the benefits of the test outweigh these risks. Your doctor or nurse will explain all the risks of having an ERCP and what to look out for.

Inflammation of the pancreas (pancreatitis)

You may have inflammation of the pancreas after this test. This can cause pain in your tummy (abdomen). Your doctor can give you painkillers to help control this. It's important to tell your nurse or doctor if you get pain in your abdomen. 

Inflammation of the pancreas can also be severe. You might need to stay in hospital for some days if this happens.


There's a risk of infection with this test. If you get a temperature or generally feel unwell contact your doctor.  


There may be some bleeding from having an ERCP which usually stops on its own. In some cases this can be severe and you will need medicine to stop it and maybe a blood transfusion. 

Allergic reaction

There is a risk of having an allergic reaction to the sedation or dye. This can cause problems with your breathing, heart rate and blood pressure. If this happens, the staff will give you medicines to control the reaction. 

Tear in your bowel

Very rarely there is a small tear (perforation) in the first part of your small bowel. If this happens it’s likely you would need surgery to repair the tear.

Exposure to radiation

The amount of radiation you receive from the x-rays during the test is small and doesn't make you feel unwell. Talk to your doctor if this worries you.

When to contact a doctor

Contact the hospital where you had the ERCP or go the accident and emergency department (A&E) if you have:

  • ongoing or severe pain in your abdomen
  • a high temperature
  • yellowing of the skin (jaundice), if you didn't have it before
  • black poo (this can be a sign of blood in your poo)
  • being sick and are unable to stop

Getting your results

You should get your results within 1 or 2 weeks. 

Waiting for results can make you anxious. Ask your doctor or nurse how long it will take to get them. Contact the doctor who arranged the test if you haven’t heard anything after a couple of weeks.

You might have contact details for a specialist nurse who you can contact for information if you need to. It may help to talk to a close friend or relative about how you feel.

For information and support, you can call the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, Monday to Friday.
Last reviewed: 
07 Jan 2020
  • ERCP Endoscopic Retrograde Cholangiopancreatography Beyond The Basics
    UpToDate, Accessed 2018

  • Biliary cancer: European Society of Medical Oncology clinical practice guidelines for diagnosis, treatment and follow up
    Valle J W and others
    Annals of Oncology, 2016 (supplement 5): v27-v38

  • ERCP: The Fundamentals (2nd Edition)
    P B Cotton and J Leung
    Wiley Blackwell, 2015

  • ERCP (2nd Edition)
    T H Baron and others
    Elsevier Saunders, 2013

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