This information from Great Ormond Street Hospital (GOSH) explains about the gastroscopy procedure, what it involves and what to expect when your child comes to GOSH for treatment. You may also hear the procedure called an oesophagogastroduodenoscopy or OGD.A gastroscopy (also called an oesophagogastroduodenoscopy or OGD) is a test that allows the doctor to look at the oesophagus, stomach and duodenum for any abnormalities. This is to confirm or rule out a condition or diagnosis. A gastroscopy is the ‘gold standard’ way of assessing the internal gut wall.

An endoscope (a flexible tube with a camera on the end) is passed into the mouth to look at the lining of the gut and to take tiny biopsies (samples of tissue). The test lasts about 15 to 30 minutes and the results will be available in two to three weeks.

What will happen?

At home

  • If your child is on the morning list
    • Stop food and milk at 2.30am
    • Do not drink any water or fluid from 6.30am.
  • If your child is on the afternoon list
    • Stop food and milk at 7.30am
    • Do not drink any water or fluid from 11.30am.
  • Some children need to be in hospital to prepare for the test.
  • Please bring any medicines that your child is taking.
  • It is important to keep giving your child food and drink until those times to ensure they remain well-hydrated. This may involve waking your child in the night to give them a drink.

At hospital

  • A doctor will check that your child is well enough to have the test.
  • If not done already, the doctor will explain the test and ask you to sign a consent form.
  • A nurse will put a cannula (thin plastic tube) in a vein.
  • Your child will be taken to the Gastroenterology Investigation Suite for the test.
  • Your child will be given an anaesthetic (medicine to make them sleep).
  • You will be asked to leave the room once they are asleep.
  • The doctor will carry out the test.
  • Your child will wake up gradually from the anaesthetic.
  • Your child can drink, eat and pass urine.
  • If there are no problems, you and your child can go home. 

Back home afterwards

  • Please continue to encourage your child to drink.
  • We will contact you to make arrangements to discuss the results.

Are there any risks?

The chance of any problems occurring is minimal but it is important that you are aware of them.
Your child may

  • have a sore throat.
  • have damage to the bowel wall.
  • vomit small spots of blood up to 72 hours after the test – this is normal as biopsies have been taken.
  • have abdominal pain due to excess wind up to 48 hours after the test.
  • have an infection, especially if your child has a central venous catheter.
  • feel dizzy or sick up to 24 hours after the test due to the anaesthetic.
Please contact your family doctor (GP) or local hospital if these symptoms carry on for longer than expected or your child

  • vomits large amounts of bright red blood or clots. 
  • has severe abdominal pain and a swollen tummy.
  • becomes generally unwell.
  • refuses to eat or drink.
  • is unusually sleepy or difficult to wake up.
Compiled by:
The Gastroenterology Investigation Suite in collaboration with the Child and Family Information Group
Last review date:
April 2015