1. 8620-Gastroscopy (EN)

A gastroscopy is an internal examination of the oesophagus, stomach and duodenum. This leaflet explains what this examination entails and how you should prepare for it.


During a gastroscopy, a gastroenterologist examines the oesophagus, stomach and duodenum using an endoscope (a small flexible tube with a small camera attached to it). The camera’s images are displayed on a monitor.


There must be no food in your oesophagus or stomach during this examination. To avoid serious complications such as pneumonia, you must fast before the examination. In practice, this means:

  • Up to six hours before the procedure, having only a light breakfast such as two rusks or two crackers or one sandwich. Up to 2 hours before the procedure, drinking only clear liquids (coffee without milk, tea, water or apple juice).
  • As from two hours before admission to hospital, having nothing else to drink.
  • If you are using medication, you may take it with a small bottle of water.

Below is an example

You are expected at the hospital at 15.00. This means you must not eat anything after 09.00. You must not drink anything after 13.00.

Special points to consider

  • If you have diabetes, ask, when making the appointment for the examination, if you can come early in the morning.
  • If you taking blood thinners, contact the doctor who prescribed that medication at least five days before the examination.
  • If you have an artificial heart valve, contact the doctor who requested the examination before undergoing it.
  • It’s a good idea to bring someone with you who can also drive you home afterwards.


Local anaesthetic

If you are generally prone to gagging, you may be given a local anaesthetic (throat spray or gel) during the examination so that you feel the endoscope less and will gag less. You should then wait for about 30-45 minutes after the examination before eating and drinking, otherwise you may choke.

Mouth guard

A mouth guard will be inserted between your teeth (upper and lower jaw) to protect the endoscope. If you have a bridge or a crown, let one of the staff performing the procedure and/or a doctor know.

If you have have dentures,  remove them at the beginning of the examination.

Introduction of the endoscope

During the examination, you will be lying on your left side on an examination table. The endoscope is covered with a special jelly. The doctor inserts the endoscope through your mouth and asks you to swallow. This can cause an unpleasant gagging sensation. The doctor may then push the tube further down himself.

Air and burping

Every now and then, the doctor will introduce a little air into the stomach. This causes the stomach to distend, allowing the doctor to have a good look at the stomach lining. This will probably cause you to burp during (and after) the procedure. This is perfectly normal and there is no need to feel embarrassed. The doctor may also aspirate fluid and air through the endoscope. If necessary, he may remove some pieces of mucosa for further analysis. This is not painful.

The examination will last around five minutes.

After the examination

You can start eating and drinking again as normal after the examination, unless the doctor has made other arrangements with you.

The doctor who carried out the examination will give you the provisional results. The final results will be sent to the GP who requested the examination.

If your GP requested the examination, he will discuss the next steps with you. You may contact him five working days after the examination for the final results.

If your medical specialist requested this examination, you will be given a follow-up appointment at the outpatients’ clinic, if you need one.

Possible complications

A gastroscopy is a safe procedure. Nevertheless, complications, for example, pneumonia can occur on occasion. This can happen if you choke on stomach contents. That’s why it is important to fast before you come in.


If you experience any symptoms after the examination, please contact the doctor who performed it. Outside office hours, you may contact the gastroenterologist on duty through reception.


If you have any questions, please call the Endoscopy Department of the Gastroenterology Outpatients’ Clinic.


+31 (0) 88 624 33 20 (available from Monday to Friday from 08.30 to 10.30)

Your appointment confirmation shows you which location you are expected to attend. If you are unable to make your appointment, let us know as soon as possible and we will schedule a new one.

Deze brochure is ook beschikbaar in Nederlands: folder Gastroscopie.

Laatst gewijzigd 11 juli 2023 / 8620

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