• A gastroscopy is a test to check inside your throat, food pipe (oesophagus) and stomach, known as the upper part of your digestive system.
  • This test can help find what's causing your symptoms.
  • A long, thin, flexible tube with a small camera inside it is passed into your mouth then down your throat and into your stomach.
  • A gastroscopy can also be used to remove tissue for testing (biopsy) and treat some conditions such as stomach ulcers.

Important: Your pain relief options

You’ll be offered medicine called sedation which can make you feel very relaxed and sleepy. You’ll also be offered medicine to numb your throat.

Why should it be done?

Why a gastroscopy is done

A gastroscopy can be done to check what’s causing your digestive symptoms, treat some conditions or check for cancer.

The cause of your digestive symptoms

A gastroscopy can be done to check what’s causing your digestive symptoms, such as:

  • difficulties swallowing or pain when swallowing (dysphagia)
  • indigestion, heartburn or stomach pain that does not go away or keeps coming, even if you take medicine
  • you keep feeling sick (nausea) or being sick (vomiting), or both
  • vomiting blood
  • your poo is black and sticky, like tar (there may be blood in it from your stomach)

Treating problems

A gastroscopy can sometimes also be used to treat problems with your digestive system. A gastroscopy can help:

  • widen your food pipe (oesophagus) if it’s too narrow and causing pain or difficulties when you swallow
  • stop bleeding inside your stomach or oesophagus
  • remove growths
  • with feeding if you’re unable to eat normally (a gastroscopy can help doctors place a feeding tube into your stomach)

Checking for cancer

A gastroscopy can be used to check for some types of cancer, such as:

  • stomach cancer
  • oesophageal cancer – this is cancer of the food pipe (oesophagus), the tube connecting your mouth to your stomach

During a gastroscopy a small sample of tissue can be removed from your stomach or oesophagus for testing. This is called a biopsy.

The biopsy is tested to see if there are any cancer cells in it.

Getting ready

Once you've been referred for a gastroscopy, you’ll get a letter in the post or by email, telling you when the gastroscopy will happen.

Some hospitals will phone you to book your appointment , but you should also get a letter. Call the hospital if you do not get one.

Your letter will tell you:

  • when you should stop eating and drinking before the test
  • about some of the medicines you may be offered before having the test
  • how long you may have to wait for your results


If you're pregnant, or taking any medicines, let the hospital know. If you have a pre-operative assessment by phone or in person, you can tell the staff then.

If you do not have an assessment, contact the hospital to tell them. Contact details should be provided in your letter or email.

Getting ready for the procedure

On the day of the gastroscopy, you’ll need to stop eating at least 6 hours before the test.

You may be able to have small sips of water. Your letter will give you more details about eating and drinking on the day.

You’ll be offered medicine called sedation to relax you just before a gastroscopy begins. If you choose to have sedation, you’ll need to arrange for someone to collect you after the gastroscopy and take you home.

The medicine can stay in the body for around 24 hours, which makes certain activities unsafe, such as driving. You will need to arrange for someone to stay with you during this time.

You might also need to take the next day off work, depending on the type of work you do.

What happens on the day

What happens during a gastroscopy

On the day of the gastroscopy you’ll need to stop eating at least 6 hours before the test.

You may be able to have small sips of water. Your letter will give you more details about eating and drinking on the day.

You should bring along the details of medicines you take. Follow any instructions the hospital gives you about taking medicines.

When you arrive

You'll speak with a nurse about what's going to happen. They’ll ask some questions about your health and medical history.

You may be offered something to make you more comfortable and make the test easier, such as:

  • local anaesthetic spray – to numb the back of your mouth and inside of your throat
  • sedation – medicine given through a small tube in your arm to help you relax


You must not drive for 24 hours if you have sedation. Someone will need to pick you up from hospital in a car or taxi.

Giving consent

A nurse or specialist will explain possible risks.

In rare cases, people may:

  • have a reaction to the sedation
  • have some bleeding afterwards
  • have an infection after the procedure

You'll be asked to sign a consent form. This is to confirm you understand the risks and agree to have the procedure.

It's important to remember these things are rare. If anything happens, the team will take care of you.

The procedure

It should take 15 to 45 minutes to have your gastroscopy.

But you might be at the hospital for around 4 hours from the time you get there until you go home.

What happens -
A thin, flexible tube with a small camera inside goes into your mouth and down your throat into your stomach.

What it might feel like -
You may feel like you want to be sick. This should stop once the tube reaches your stomach. Sedation can help prevent this.

What happens -
Air is pumped in to inflate your stomach.

What it might feel like -
You may feel bloated and might burp a few times

What happens -
A sample of cells may be taken.

What it might feel like -
You will not feel anything if this happens.

A gastroscopy should not be painful. But you can ask for the procedure to be stopped at any time.

After a gastroscopy

After the gastroscopy is finished you will be moved to a recovery room.

You should be able to go home as soon as you feel well enough to. For most people, this will be within a few hours.

If you have sedation, you’ll need someone to take you home and stay with you for 24 hours.

You should also avoid doing any of the following for 24 hours after sedation:

  • drinking alcohol
  • driving
  • operating machinery
  • signing important documents

If you have a local anaesthetic spray you should wait an hour before eating or drinking.

You may have some stomach and throat pain after a gastroscopy. This is normal and should pass in a few hours.

Call 111, or the hospital where you had a gastroscopy, if:

You have any of these things after a gastroscopy:

  • a high temperature, or you feel hot or shivery
  • poo that’s dark or black, like tar
  • shortness of breath
  • you keep being sick

Call 999 or go to your nearest A&E department if:

you’re vomiting blood
you have severe stomach or chest pain, or stomach or chest pain that gets worse

Find your nearest A&E


A doctor or nurse may explain the results of the gastroscopy to you before you leave hospital. If you had a biopsy, you’ll need to wait for the results.

They’ll also let you know if any extra treatment was done during the gastroscopy.

You may be given a follow-up appointment to talk about your results and discuss possible treatments that could help you.

Biopsy results

If you had cells removed for testing, called a biopsy, it can take up to 2 months to get the results.

If doctors think you may have cancer you’ll get the results in 2 weeks.

If your results say you have cancer, you’ll be put in touch with a specialist cancer care team.

Support is available

For many people a gastroscopy will not find anything to worry about.

But it might help to speak to someone if you're feeling worried about your results.

You can get in touch with charities such as:

The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website
Last Updated: 05/03/2024 11:18:38