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This page is about having an endoscopy, which is a test that looks at the inside of your body - most commonly the digestive system. You can find the following information


A quick guide to what’s on this page

What is an endoscopy?

An endoscopy is a test that looks inside the body using a long flexible tube called an endoscope. It has a tiny camera and light on the end. Endoscopies most commonly look at the inside of the

  • Food pipe (oesophagus)
  • Stomach
  • Duodenum – the first part of the small bowel that attaches to the stomach

A doctor or specialist nurse looks down the endoscope to check for any growths or abnormal looking areas. They can also take samples (biopsies) of any abnormal looking tissues.

Having the test

You usually have an endoscopy as an outpatient. You should not eat for 6 to 8 hours beforehand. You may be allowed to drink sips of water up to 2 hours before the test.

You lie on a couch. To make it easier to swallow the tube the doctor or nurse either sprays your throat to numb it or gives you medicine to make you drowsy (a sedative). The doctor or nurse endoscopist then passes the endoscope tube down your throat.

When the test is over you will need to rest for a while. If you have a sedative you may need to stay in hospital overnight. If you don’t stay in overnight you will need someone to take you home.

The results

It may be a couple of weeks before you get the results. Contact your doctor if you have not heard anything after this time.


CR PDF Icon You can view and print the quick guide for this page about endoscopy.



What an endoscopy is

An endoscopy is a test that looks inside the body. The endoscope is a long flexible tube which has a tiny camera and light on the end of it. There are many types of endoscopes and the doctor uses these to look inside different parts of the body. The name of the test you have will depend on which part of the body the doctor is looking at. The diagram shows an endoscopy looking at the food pipe (oesophagus) and stomach.


Why you may have an endoscopy

You are most likely to have an endoscopy to look at the inside of your

  • Food pipe (oesophagus)
  • Stomach
  • Duodenum – the first part of the small bowel that attaches to the stomach
  • Large bowel (colon)

This test can show what is wrong if you have abnormal bleeding, indigestion or difficulty swallowing. A doctor or specialist nurse can look down the endoscope and see if there are any growths or other abnormal looking areas. Through the endoscope, the doctor or nurse can also take samples (biopsies) of any abnormal looking tissues.

Other types of endoscopy include

The links above take you to further information about these tests. This information may be within sections about specific types of cancer. For example the information about colonoscopy is within the bowel cancer section. 

The information below is about having an endoscopy of the oesophagus, stomach or small bowel (duodenum). Your doctor may call this a gastroscopy or oesophagho gastric duodenoscopy (OGD).


Having an endoscopy

About 2 days before the endoscopy you usually have a blood test to check how well your blood clots. If you are taking any medicines that change how your blood clots, it is very important to let your doctor know. These medicines include aspirin, arthritis medicines and warfarin (Coumadin). You will be told if you need to stop taking any other medication before your test.

Below is an animation showing you what happens when you have an endoscopy to look for changes in your oesophagus, stomach or small bowel.

View a transcript of the video showing you what happens when you have an endoscopy. (Opens in a new window)

You can have an endoscopy as an outpatient. A nurse will be there to support you throughout the procedure. Most people have a choice between having the test while they are awake, or after having a medicine to make them drowsy (a sedative). Your hospital may not be happy for you to have a sedative if you live alone and have no one to look after you when you go home. If you live alone but really want sedation, your hospital may allow you to stay overnight.

If you don't have a sedative, you will have a spray to numb the back of your throat and make it easier for you to swallow the endoscopy tube.

If you would prefer to be drowsy, you will have an injection of sedation just before the test to make you relaxed. You will need to take someone with you to the hospital appointment. You won't be able to drive for the rest of the day and should have someone to go home with you.

You can't eat for about 6 to 8 hours before the test so that your stomach and duodenum are empty. You may be allowed sips of water up to 2 hours before your appointment. Your doctor or nurse will give you written instructions about this beforehand, or they may arrive with your appointment letter. When you get to the clinic, you may be asked to take your upper clothing off and put on a hospital gown. Once you are ready, you get onto the bed or couch. If you are staying awake for the test, your doctor or nurse will spray the back of your throat with local anaesthetic to numb it. You then lie on your side. If you are having sedation, you will have the injection once you are lying down.

Once the sedative or throat spray has worked, the doctor or specialist nurse (endoscopist) will pass the endoscope tube down your throat to the area they want to look at. They will ask you to swallow as the tube goes down. They will put a small amount of air into your stomach, to help them see more clearly. If there are any abnormal areas, they will take pieces of tissue (biopsies) to send to the laboratory for examination under a microscope.

When the test is over you will need to rest for a while. If you had the throat spray, you will not be able to eat or drink for about an hour afterwards, until the local anaesthetic has worn off. If you had a sedative, you may not remember much (if anything) about the test once you have come round. You should be able to go home the same day.


Endoscopic ultrasound

Sometimes an ultrasound probe is attached to the endoscope tube. This is called an endoscopic ultrasound. Ultrasound uses sound waves to build up a picture of the area. This test is used to look at the wall of the oesophagus, stomach, or the gallbladder and bile duct. It may help the doctors to get a better idea of the size of a tumour and how deep it has grown into the body tissues. They may also be able to see whether nearby lymph nodes are swollen (enlarged).


Possible risks

Having an endoscopy helps doctors find out what may be causing your symptoms but, as with any medical procedure, there are possible risks. Doctors make sure the benefits of having the test outweighs these risks.

You may have bloating and some discomfort for a few hours after the endoscopy. This is due to the air the doctor or nurse puts in your stomach during the test. They remove most of the air when they take the endoscope out.

You may have a sore throat for about 24 hours after the test. If you have severe pain in your throat, chest or tummy (abdomen), you should contact the hospital. Your nurse will give you details of who to contact if you have any problems at home.

If you have sedation, there is small risk of fluid, such as saliva, going into your lungs. Your nurse will reduce this risk by removing most of the secretions from your mouth with a suction tube. There is a risk that you may react to the sedation drug, causing difficulty in breathing. Your nurse will monitor your oxygen levels during the test, and you will have oxygen through a tube that fits into your nose (nasal cannulae).

After having a biopsy, you may have some bleeding. This usually stops on its own. Very rarely, you need to go into hospital to stop the bleeding.

Very rarely, you may get a small tear in the lining of your oesophagus or stomach. If this happens, you may need antibiotics and fluids through a drip. You may need surgery to repair the tear.


The results

It can take time for test results to come through especially after a biopsy. How long will depend on why you are having the test but it may be a couple of weeks. Usually, the doctor or nurse who carries out the endoscopy dictates a report straight way. The report is typed up and sent to your specialist, who gives the results to you. If your GP has sent you for the test, the results will be sent directly to the GP surgery.

Understandably, waiting for results can make you anxious. Try to remember to ask your doctor or nurse how long you should expect to wait for the results when you are first asked to go for the test. If it is not an emergency, and you have not heard a couple of weeks after your test, ring your doctor's secretary or GP surgery to check if the results are back.

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Updated: 22 April 2015