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What is an upper GI endoscopy?

An upper gastrointestinal endoscopy (gastroscopy) is a test which allows the endoscopist to look directly at the lining of the oesophagus (gullet), the stomach and around the first bend of the small intestine – the duodenum. The gastroscope is a long flexible tube (thinner than your little finger) with a bright light on the end.

Using the gastroscope we can see a picture of the lining of your stomach on a monitor. Sometimes the endoscopist will take tissue samples (a biopsy). These biopsies are removed painlessly through the gastroscope using tiny forceps and are sent to the laboratory for analysis.

What happens during the test?

You will be seated or laid on an examination trolley and a local anaesthetic will be sprayed onto the back of your throat. This will numb your throat and make the test easier. A nurse will stay with you throughout the procedure. If you wish to have a sedative injection a needle will be put into your arm or hand at this point. You will feel relaxed and may not remember the test but it will not put you to sleep. Many hospitals now find that the test can be performed without sedation as the gastroscopes have become much smaller and are easier to swallow. If you chose an injection you will be given oxygen through a plastic mouth guard.

A small peg will be placed on your finger to measure your heart rate and oxygen level. It is necessary that you lie on your left side for the test. To keep your mouth open a plastic mouth guard will be placed between your teeth.
When the endoscopist passes the gastroscope into your stomach it is uncomfortable but it will not cause you any pain, nor will it interfere with your breathing at any time. The test usually lasts about 5 - 10 minutes. The endoscopist will carefully examine all areas of the stomach. During this time air will be passed down the tube to distend the stomach and allow clear views. Sometimes the doctor or nurse doing the test will need to take tiny samples of your stomach lining.

You are not likely to feel this. If you get a lot of saliva in your mouth the nurse will clear it using suction. When the examination is finished, the tube is removed quickly and easily.

Can there be complications or risks?

The majority of gastroscopies are very safe and uncomplicated. However, as with any procedure there is a small chance of side effects or complications.
- National studies have shown that serious complications such as drug reaction, bleeding and perforation (causing a hole) are very rare; less than 1 in 5000.
- You may suffer from a sore throat or feel some wind in your stomach. These will settle in a few days.
- There is a small risk of damage to crowned teeth or dental bridge work.
- You should also be aware that this examination is not perfect and even with a skilled endoscopist some abnormalities may be missed.

Do I have to have an endoscopy?

An alternative to a gastroscopy is a barium meal or a CT scan (computerised tomography). The disadvantages of these procedures are that specimens cannot be taken for examination. Gastroscopy is also the most accurate way of examining the oesophagus, stomach and duodenum.

What are the key things to remember?

The main thing to remember is that it is your decision. It's up to you to choose whether or not to consent to what is being proposed. Ask as many questions as you like and please express any concerns about medication, allergies or past medical history.

What should I know before deciding?

The endoscopist or heath professional will ensure you know enough information about the procedure to enable you to decide about your treatment. They will write this information on the consent form as well as discussing choices of treatment with you. We encourage you to ask questions and inform us of any concerns that you may have.
It may be helpful for you to write these down as a reminder.

Preparation for the test

To allow a clear view, the stomach should be empty. If your test is in the morning please have nothing to eat or drink from midnight of the day before.
If your test is in the afternoon please have nothing to eat or drink after 7.00am on the day of test. If your test is in the evening please have nothing to eat or drink after 11:00am on the day of the test.

The consent form

Before a doctor or healthcare professional examines or treats you, they will need to gain your consent. This will be required in writing. If you later change your mind, you are entitled to withdraw consent even after signing. A copy of the consent form will be offered to you.


Please stop all stomach treatments for at least 2 weeks before your test except: Antacids, Gaviscon, Rennies, Maalox, Aludorox, Andrews and Settlers, which are permitted. However, if your test is for a repeat gastroscopy, please continue to take your stomach treatment.

If you are taking anti-blood clotting medicines such as Warfarin, Rivaroxaban, Apixaban, Dabigatran or Clopidogrel (Plavix) please contact the Endoscopy Suite as soon as possible as these may need to be stopped before your procedure.

If you take essential medication, for example for epilepsy or a heart condition, you may take these with a little water. Please try to take them as early as possible before your test as some tablets leave a residue in the stomach, which may affect the quality of the results.

Do bring your other tablets or medicines with you so that you can take them after you have had your gastroscopy.
If you are diabetic, please refer to the 'Managing your diabetes' booklet which you received with your appointment letter.

Can I find out more about giving consent?

There is more information about consent on the NHS Choices website:

Before your appointment

Before you come to the Endoscopy Suite you should:
contact the Endoscopy Suite if you are suffering from a sore throat, cold or chest infection, as it may be necessary to postpone the test because of the risks from sedation.
bring with you any letters or cards you have received from the hospital.
bring any tablets you are currently taking. It is especially important to remember any asthma inhalers, angina sprays or diabetic medication.
follow all instructions included with this booklet.
come on time for your appointment.
you should not bring valuables or large amounts of money into hospital. We cannot accept responsibility for them.

How long will I spend in hospital?

This will depend on your individual procedure and on whether or not you choose to be sedated for your test. If you choose sedation, please allow for a stay of anything from 2 - 4 hours. If you choose not to be sedated, then your stay will be much shorter.

Please note that your appointment time is for your pre-procedure assessment and not the time of your examination.

You may find your test is delayed. We do sometimes have to deal with unexpected emergency cases and this can prevent us seeing you as quickly as we would like. We apologise if such delays happen to you. If they do we will try to keep them to a minimum and make sure you know the reason for the delay. Please be patient.

What happens after the test?

If you choose to have the test done using just a throat spray...

you will be able to go home as soon as you feel ready to leave. Since your throat has been numbed you will be asked not to have anything to eat or drink until you are able to swallow normally. This usually takes about an hour.
The back of your throat may feel sore for the rest of the day. It will settle without any treatment. You may also feel a little bloated if some of the air has remained in your stomach. This feeling should pass naturally in time without requiring treatment.

If you choose to have throat spray and sedation...

you will have to rest in the Endoscopy recovery area for approximately one hour. You may feel a little bloated with wind pains, these usually settle quickly once you have passed the wind and will not need any treatment.
Once you are fully awake the needle used to give you the sedation will be removed. You will then be able to get up and have a drink and biscuits.

The effects of the sedation can last for at least 24 hours and even though you will probably feel perfectly recovered your judgement can remain impaired during this time.

It is essential that someone comes to pick you up. Once home, it is recommended that you rest quietly for the remainder of the day and that someone stays with you overnight.

After your test

It is important that you do not: drive a car operate machinery or domestic appliances as your reaction times may be slowed drink alcohol sign legally binding agreements take sleeping medication

Getting my results

The endoscopist may be able to tell you the results of your tests straight away. However, if you had sedation you may not remember what has been said. To make sure you have had and understood your results, the recovery nurse will give them to you again when you are fully awake.

If a biopsy has been taken or if polyps have been removed these have to go to the laboratory and the results from these tests may take several days. A copy of the procedure report will be sent to your GP/referring doctor.
Further details of the examination and any necessary treatment should be discussed with your GP in 10 to 14 days or at your next outpatient appointment.

Frequently Asked Questions

If my symptoms have stopped before the gastroscopy/OGD, should I still come for the test?

Yes. It is important that you still come for the test. Your doctor has organised this test to ensure you have no problems in your oesophagus (gullet), your stomach and your duodenum. Although your symptoms may have gone, it important to have a look to ensure all is clear.

When can I get back to my normal activities?

You should be ready to get back to your normal activities by the next day.

Will it hurt?

No, these examinations are not painful. You may feel some discomfort from the air that is pumped into the stomach so that the Endoscopy can view the lining adequately. Some patients find the air used to inflate the stomach slightly uncomfortable. It should not hurt. A mild sedative is available to you should you wish to have one.

Can I drive home after the procedure if I choose to have sedation?

If you have sedation you will not be allowed to drive home and must arrange for someone to accompany you and drive you home. Medication given during the test will prohibit you from driving until 24 hours after your examination. Please do not plan to take public transport home. If you are unable to arrange transportation we can arrange a taxi to take you home, however, you are responsible for the fare. You will need a responsible adult with you for at least 12 hours.

Will I get my results on the day?

Upon completion of the gastroscopy/OGD the findings will be discussed with you. We will be able to tell you any visual findings, however any biopsies will need to be sent to the laboratory for testing, and this can take up to 3 weeks. A copy of the procedure report will be sent to your referring doctor and your GP.

Is there anything I should look out for when I go home?

If you have any problems when you go home, or are feeling worse than you expected, please contact the One Health team or Hospital/Treatment Centre on the telephone numbers given to you on discharge

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We believe it’s important to share experiences of patients who have suffered with gastrointestinal issues. Many charities feel the same way — and this piece contains some direct quotes featured by a charity doing great work in this area, Guts Charity. Below you can discover Phil and William‘s story that they shared with Guts Charity about their experience with Diverticular Disease, a condition that we treat at One Health.

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