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Having An Upper GI Endoscopy

You have been advised to have an upper GI endoscopy to help find the cause of your symptoms. The test is sometimes called a “gastroscopy”, “OGD” or simply an endoscopy. This information sheet has been produced to answer some of the questions you have about the procedure.

This information sheet may not answer all your queries, but if you have any worries or concerns, please do not hesitate to contact your consultant’s office to go over these.


Upper GI endoscopy is a test which allows the endoscopists to look directly at the lining of the oesophagus (“the gullet”), the stomach and around the first bend of the small intestine (“the duodenum”). In order to do the test an endoscope is passed through your mouth into the stomach. The endoscope is a long flexible tube with a bright light and video chip at the end. The view through the endoscope is often displayed on a TV screen, so you may be able to watch the procedure yourself. The endoscopists gets a clear view of the lining of the stomach and can check whether or not any disease is present. Sometimes the endoscopists takes a biopsy – a sample of tissue for analysis in the laboratory. The tissue is removed painlessly through the endoscope, using tiny forceps.

What To Expect:

The preparation

To allow a clear view, the stomach must be empty. You will therefore be asked not to have anything to eat or drink for at least six hours before the test. When you come to the department, the endoscopists will explain the test to you and will ask you to sign a consent form. This is to ensure that you understand the test and its implications. Please tell the endoscopists or nurse if you have previously had any allergies or bad reactions to drugs or other tests. They will also want to know about any previous endoscopies you have had. If you have any worries or questions at this stage, do not be afraid to ask. You may be asked to undress and to put on a hospital gown. It will also be necessary for you to remove any false teeth, but these will be kept safely for you until after the examination has been completed.

During the test

In the examination room you will be made comfortable on a couch resting on your left side. A nurse will remain in the room during the course of the examination. Some endoscopists may spray a local anaesthetic on the back of your throat or give you a tablet to suck to numb the area. You may also be given an injection to make you feel sleepy and relaxed. A significant number of tests, however, are performed without sedation. To keep your mouth slightly open, a plastic mouthpiece will be put between your teeth. When the endoscopists passes the endoscope into your stomach it will not cause you any pain, nor will it interfere with your breath at any time. It may take up to fifteen minutes to examine all areas of the stomach carefully. During this time some air will be passed down the tube to distend the stomach and allow the endoscopists a clearer view – the air is sucked out at the end of the test. If you get a lot of saliva in your mouth, the nurse will clear this for you using a sucker. When the examination if finished, the endoscope will be removed quickly and easily.


There is a slight risk of damage to teeth, crowns or bridges.

After the Test:

You will be left to rest in the unit. You will be given a drink, but if you have had your throat numbed by a spray or lozenge, you will have to wait until your swallowing reflex is back to normal. This usually takes just over an hour. After this you can eat and drink normally, however the back of the throat may feel a little sore for the rest of the day. You may also feel a little bloated if some of the air has remained in your stomach. Both these discomforts will pass and there is no need for any medication.

Going Home:

If you are going home after the test, and you have had sedation, it is essential that you have someone come and collect you. Once home, it is important to rest quietly for the remainder of the day. Sedation lasts longer than you think, so if you have been given sedation, you should not drive a car, operate machinery or drink alcohol. The effects of the injection for sedation should have worn off by the next day when most patients are able to resume normal activities.


The consultant will either ask you to arrange a follow up consultation to go over your results or they may write to you with them. The consultant will have spoken to you following your Upper GI Endoscopy before you left to go home, but if you were given sedation, you may not remember the conversation. Also a copy of the result will also be sent to your GP or the hospital specialist who referred you.