Having an ERCP

ERCP (endoscopic retrograde cholangio pancreatogram)

During an ERCP, a flexible tube (endoscope) with a camera on the end is put into your mouth, down your food pipe (oesophagus), into your stomach and into the first part of your small intestine.

The procedure lasts between 15 minutes and 1 and a half hours. The average time is 30 minutes.

An ERCP can be used to:

  • take samples of your cells through brushings or biopsies, which will be examined in a laboratory
  • put small plastic or metal tubes (stents) into your bile duct or small intestine (duodenum), to drain the bile or treat a blockage affecting the flow of food out of the stomach
  • help remove pancreatic stones or to put a stent into a narrowed pancreatic duct, which can be help pain

Read more about how an ERCP is used to diagnose and treat conditions

Preparing for ERCP

Wear loose-fitting clothes on the day of the ERCP.

Before you have the ERCP, you will have a blood test to check the clotting of your blood, and your blood count.

Instructions for sedation and general anaesthetic

ERCP is usually done with sedation or a general anaesthetic.

Sedation will relax you and might make you sleepy (drowsy), but you will not be asleep. You will hear what is said to you and can respond to any instructions you are given.

General anaesthetic gives a state of controlled unconsciousness. This is like being asleep and you do not feel pain.

If you are leaving hospital within 24 hours after the ERCP, you must have someone to take you home and stay with you overnight.

They must be over 18 years old and should come with you for the appointment, or be contactable by phone when you are ready to leave the hospital.

If you do not have someone to take you home and stay with you overnight, your procedure might be cancelled.

If you cannot arrange for someone to collect you, please contact us to discuss alternative arrangements.

Eating and drinking

  • Do not eat anything for 6 hours before the ERCP. This is so the doctor has a clear view with the camera.
  • Do not drink anything for 4 hours before your appointment.
  • You can have small sips of water for up to 2 hours before.

Usual medicines

You should have had a chance to talk to your doctor or nurse about any medicines you are taking before your procedure.

Let your doctor or nurse know if:

  • you are taking any regular medicines, this includes medicines you buy at a pharmacy or shop and any herbal or homeopathic medicines
  • you have allergies to any medicines
  • you are taking antiplatelet or anticoagulant medicine that thin your blood (such as aspirin, clopidogrel, warfarin or rivaroxaban), as you might need to stop taking these medicines for a short time before your procedure
  • you are taking sedatives, chronic pain medicine, or medicines for diabetes, as you might need to change the dose of these medicines for a short time before the procedure

Keep taking all of your medicines as usual, unless you have been told otherwise by the doctor or endoscopy nurse.

More information on stopping any medicines will be given to you when you have a pre-assessment appointment.

If you have any questions about your medicines, please speak to your doctor or nurse.

Arriving at the endoscopy unit

When you arrive, please give your name to the receptionist. You will be asked to wait in the waiting area until you are seen by an endoscopy nurse.

The nurse will ask you about your medical history. Please tell them if you have had any reactions or allergies to other procedures in the past.

You will be asked to take off all your jewellery. This is because you should not wear any metal during the procedure. You might wish to leave any valuable jewellery at home, as we cannot be responsible for any valuables lost while in the unit. 

You will be asked to remove all of your clothing and change into a gown and some dignity disposable underwear. You might want to bring your dressing gown and slippers with you (we do supply non slip socks).

Once you are ready, you will be taken to the second waiting area, signposted ‘sub wait area’.

Your doctor will explain more about the procedure and answer any questions you have.

Waiting times

Our endoscopy teams run up to 5 procedure rooms at the same time, so a person who arrived after you might be called in before you. This does not mean you have been forgotten, it means that the other person is on a different list to you.

We do everything we can to avoid keeping you waiting any longer than necessary. However, because every procedure takes a different length of time, sometimes it is hard to give exact timings.

We also deal with emergencies. These can take priority over your appointment, and we might have to ask you to wait.

We will update you regularly on to how long you are likely to be with us. Please be prepared to be with us for the whole morning or whole afternoon, depending on when your appointment is.

Please be patient with us and check at the reception desk if you are concerned.

During an ERCP

The procedure lasts between 15 minutes and 1 and a half hours. The average time is 30 minutes.

You will usually be given an antibiotic to take 1 hour before the ERCP. You can swallow this with a small amount of water.

  1. A nurse will attach monitors to one of your fingers. These record your pulse, oxygen level, blood pressure and heart rhythm. 
  2. You might be given a local anaesthetic throat spray to help numb your throat.
  3. You will need to lie on your left side.
  4. A plastic mouthguard will be placed in your mouth. This allows the tube to pass through your mouth, and for oxygen to be given to you during the procedure.
  5. You will be given an injection of sedation and painkiller through a small needle in the back of your hand or arm.
  6. A nurse will sit by your head and monitor you for the whole procedure.
  7. Once you are sleepy, a flexible tube (endoscope) with a tiny camera on the end of it will be passed through your mouth, into your stomach and the top part of your small intestine.
  8. The doctor will put a fine wire through the endoscope and into the bile ducts.
  9. They will inject a dye through the tube, which shows up on the X-ray.
  10. X-rays of various parts of your biliary system will be taken.

Samples (biopsies) might be taken from the bile ducts using a small brush or forceps. A plastic or metal tube (stent) might be put in to help with the drainage of bile or pancreatic juice. 

If the ERCP is being done to remove stones from the bile or pancreatic duct, a small cut (sphincterotomy) might be made in the lower end of the bile duct to allow a fine tube to pass through. This allows stones to be removed, or any stones that might block the bile duct in future to easily pass into the intestine.

Doctors in training

Doctors in training are likely to be present during your procedure. They will be fully supervised with the consultant standing next to them. They will only do parts of the procedures that they have been trained in.


An ERCP is done with sedation or, in some cases, with a general anaesthetic. You will have been told if you need to have a general anaesthetic.

You'll be given a painkiller before your procedure, to make you as comfortable as possible. You might have short periods of discomfort or pain from certain parts of the procedure. This should not last long.

We will give you pain medicine in your bottom (a suppository) before the end of the procedure. This will reduce the risk of pancreatitis.

You might have cramps and tummy (abdominal) pain after the procedure. This is due to the air used to inflate your small intestine. You can take simple painkillers, such as paracetamol after the ERCP.

Read more about side effects after an ERCP

Tell your doctor or nurse immediately if:

  • you have severe tummy pain after an ERCP

If you are at home, contact your GP or go to the nearest emergency department). Take your endoscopy report with you.

Resource number: 2559/VER5
Last reviewed: December 2021
Next review: December 2024

Contact us

If you have any questions or concerns about having an ERCP and you are in hospital, please speak to your nurse.

If you are at home and have any questions, or you need to cancel or change your appointment, please contact the endoscopy unit.

Phone 020 7188 8887 Monday to Saturday 9am to 5pm.

You can also contact:

In an emergency

Out of hours (evenings and weekends) phone 020 7188 7188 and ask to be put through to the on-call gastroenterology registrar (via Rota watch).

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Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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