What is an upper GI endoscopy?

Upper GI endoscopy procedure diagram

An upper gastrointestinal (GI) endoscopy is a procedure to look at the inside of your oesophagus (gullet), stomach and duodenum using a flexible telescope (see figure 1). This procedure is sometimes known as a gastroscopy or simply an endoscopy.

Your doctor has recommended an upper GI endoscopy. However, it is your decision to go ahead with the procedure or not.

This information about the benefits and risks will help you to make an informed decision. If you have any questions ask your doctor or the healthcare team.

What are the benefits of an upper GI endoscopy?

Your doctor is concerned that you may have a problem in the upper part of your digestive system. An upper GI endoscopy is a good way of finding out if there is a problem.

If the endoscopist (the person doing the endoscopy) finds a problem, they can perform biopsies (removing small pieces of tissue) to help make the diagnosis.

Are there any alternatives to an upper GI endoscopy?

Your doctor has recommended an upper GI endoscopy as it is the best way of diagnosing most problems with your upper digestive system.

A barium swallow or meal is an x-ray test of your upper digestive system. This test is less invasive but provides less detail about the lining of the gut and if this highlights a possible problem you may still need an upper GI endoscopy to perform biopsies.

A urea breath test can be used to detect Helicobacter pylori, a bacteria that may cause stomach ulcers.

What does the procedure involve?

  • Before the procedure

If you take warfarin, clopidogrel or other blood-thinning medication, let the endoscopist know at least seven days before the procedure. Do not eat in the six hours before the procedure. You may drink small amounts of water up to two hours before. This is to make sure your stomach is empty so the endoscopist can have a clear view of your stomach. It will also make the procedure more comfortable. If you have diabetes, let the healthcare team know as soon as possible. You will need special advice depending on the treatment you receive for your diabetes.

The healthcare team will carry out a number of checks to make sure you have the procedure you came in for. You can help by confirming to the endoscopist and the healthcare team your name and the procedure you are having.

The healthcare team will ask you to sign the consent form once you have read this document and they have answered your questions.

  • In the endoscopy room

An upper GI endoscopy usually takes about 10 minutes.

Once you have removed any false teeth or plates, the endoscopist will spray your throat with some local anaesthetic and ask you to swallow it. This can taste unpleasant.

If appropriate, the endoscopist may offer you a sedative to help you to relax. If you decide to have a sedative, it will be administered through a small needle in your arm or the back of your hand.

The endoscopist will ask you to lie on your left side and will place a plastic mouthpiece in your mouth.

The healthcare team will monitor your oxygen levels and heart rate using a finger or toe clip. If needed oxygen will be given through a mask or small tube in your nostrils.

If at any time you want the procedure to stop, raise your hand. The endoscopist will end the procedure as soon as it is safe to do so.

The endoscopist will place a flexible telescope (endoscope) into the back of your throat. They may ask you to swallow when the endoscope is in your throat. This will help the endoscope to pass easily into your oesophagus and down into your stomach. From here the endoscope will pass into your duodenum.

The endoscopist will be able to look for problems such as inflammation or ulcers. They will be able to perform biopsies and take photographs to help make the diagnosis.

The procedure is not painful but your stomach may feel bloated because air is blown into your stomach to improve the view.

What complications can happen?

The healthcare team will try to make the procedure as safe as possible but complications can happen. Some of these can be serious and can even cause death (risk: 1 in 25,000). The possible complications of an upper GI endoscopy are listed below. Any numbers which relate to risk are from studies of people who have had this procedure. Your doctor may be able to tell you if the risk of a complication is higher or lower for you.

  • Sore throat. This gets better quickly.
  • Allergic reaction to the equipment, materials or medication. The healthcare team is trained to detect and treat any reactions that might happen. Let the endoscopist know if you have any allergies or if you have reacted to any medication or tests in the past.
  • Breathing difficulties or heart irregularities, as a result of reacting to the sedative or inhaling secretions such as saliva. To help prevent this from happening, your oxygen levels will be monitored and a suction device will be used to clear any secretions from your mouth. Rarely, a heart attack (where part of the heart muscle dies) or stroke (loss of brain function resulting from an interruption of the blood supply to your brain) can happen if you have serious medical problems.
  • Infection. It is possible to get an infection from the equipment used, or if bacteria enter your blood. The equipment is sterile so the risk is low but let the endoscopist know if you have a heart abnormality or a weak immune system. You may need treatment with antibiotics. Let your doctor know if you get a high temperature or feel unwell.
  • Making a hole in your oesophagus, stomach or duodenum (risk: 1 in 2,000). The risk is higher if there is an abnormal narrowing (stricture) which is stretched (dilated). You will need to be admitted to hospital for further treatment which may include surgery.
  • Damage to teeth or bridgework. The endoscopist will place a plastic mouthpiece in your mouth to help protect your teeth. Let the endoscopist know if you have any loose teeth.
  • Bleeding from a biopsy site or from minor damage caused by the endoscope. This usually stops on its own.
  • Incomplete procedure caused by a technical difficulty, food or blockage in your upper digestive system, complications during the procedure, or discomfort. Your doctor may recommend another endoscopy or a different test such as a barium meal.

You should discuss these possible complications with your doctor if there is anything you do not understand.

How soon will I recover?

If you were not given a sedative, you should be able to go home and return to normal activities straightaway. Do not eat or drink for at least the first hour.

If you were given a sedative, you will be transferred to the recovery area where you can rest. You will usually recover in about an hour, but this depends on how much sedative you were given. Once you are able to swallow properly, you will be given a drink. You may feel a bit bloated for a few hours but this will pass.

If you were given a sedative, a responsible adult should take you home in a car or taxi and stay with you for at least 12 hours. Be near a telephone in case of an emergency.

Do not drive, operate machinery or do any potentially dangerous activities (this includes cooking!) for at least 24 hours and not until you have fully recovered feeling, movement and co-ordination. You should also not sign legal documents or drink alcohol for at least 24 hours. You should be able to return to work the next day unless you are told otherwise.

The healthcare team will tell you what was found during the endoscopy and discuss with you any treatment or follow-up you need. Results from biopsies will not be available for a few days so the healthcare team may arrange for you to come back to the clinic for these results.

Once at home, if you get chest or back pain, difficulty breathing, pain in your abdomen, a high temperature, or if you vomit, contact the endoscopy unit. In an emergency, call an ambulance or go immediately to your nearest Emergency department.

  • Lifestyle changes

If you smoke, stopping smoking will improve your long-term health.

Try to maintain a healthy weight. You have a higher risk of developing complications if you are overweight.

Regular exercise should improve your long-term health. Before you start exercising, ask the healthcare team or your GP for advice.


An upper GI endoscopy is usually a safe and effective way of finding out if there is a problem with the upper part of your digestive system. However, complications can happen. You need to know about them to help you to make an informed decision about the procedure. Knowing about them will also help to detect and treat any problems early.


Author: Prof Simon Parsons DM FRCS (Gen. Surg.)
Illustrations: Medical Illustration Copyright © Medical-Artist.com

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