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The goal of a gastroscopy is to explore the upper part of your digestive system. During a gastroscopy, a long, thin, flexible tube with a small camera and light inside is passed into your mouth to inspect your food pipe (oesophagus), stomach and duodenum (the initial c-shaped section of the small intestine).

Also known as: OGD (oesophago-gastro-duodenoscopy)

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What is a gastroscopy?

The goal of a gastroscopy is to explore the upper part of your digestive system. During a gastroscopy, a long, thin, flexible tube with a small camera and light inside is passed into your mouth to inspect your food pipe (oesophagus), stomach and duodenum (the initial c-shaped section of the small intestine). During a gastroscopy, tissue samples (biopsies) can also be taken and some conditions, such as stomach ulcers, can be treated.

You might need a gastroscopy if you experience symptoms such as:

  • Indigestion which does not go away with treatment
  • Difficulty or pain when swallowing
  • Chest or upper tummy pain
  • Nausea and/or vomiting
  • Blood in vomit or dark, tar-like blood in poo

A gastroscopy is also a valuable diagnostic tool for assessing various gastrointestinal conditions, including:

  • Peptic ulcers – these are sores that develop in the lining of your stomach or duodenum
  • Coeliac disease
  • Barrett’s oesophagus (abnormal cells in your oesophagus)
  • Cancer, such as stomach cancer or oesophageal cancer

The procedure is usually performed on an outpatient basis, meaning you can go home the same day, and takes between 15 – 45 minutes. Before the procedure, patients are typically given a sedative to help them relax, and a local anaesthetic spray is applied to the back of the throat to reduce discomfort.


If you are worried about your symptoms or your GP has referred you, get in touch and we will book you in with one of our specialist consultants.

During your initial appointment, your doctor will ask about your symptoms, any test results, and take a detailed medical history. If you have copies of previous test results or treatment plans, please bring these with you. After this, they will talk through your options and let you know whether you should have additional tests. If a gastroscopy is recommended, your doctor will explain the procedure thoroughly, including the risks and benefits. We encourage you to ask questions and it may be helpful to write these down beforehand as a reminder.

If you decide to have a gastroscopy, you will be given some instructions to follow prior to the procedure, such as:

  • Fasting – to allow for a clear view of the upper gastrointestinal tract, you will typically be instructed not to eat or drink anything for 6 to 8 hours before the procedure. It is very important to comply with the fasting instructions as your stomach must be empty for the test. If your stomach is not empty, there is a risk of aspiration (vomit inhaled into the lungs), which can be very serious.


  • Medication adjustments – inform your doctor about any medications you are currently taking, such as blood thinners, antiplatelet drugs, or medications that affect blood clotting. In some cases, your doctor may advise you to adjust or temporarily stop certain medications before the procedure. Remember to bring any prescription medications with you when you come for your gastroscopy.

When you arrive at our hospital, we will show you to your private room and our nursing team will check your vital signs, including weight, blood pressure and temperature. You will also have the choice to change into a hospital gown. Finally, your doctor will see you before your procedure and check that you’re still happy to go ahead.


To start, you will be given the option of a sedative to help you relax, and a local anaesthetic spray to numb the back of your throat. Once your throat is numb, it may feel as though you can’t swallow. Try not to panic. You will be able to swallow but may not feel it.

The procedure will start with you lying on a couch and you will be given a mouth guard to protect your teeth and prevent damage to the endoscope.

The gastroenterologist will gently insert the endoscope into your mouth. This is a thin, flexible tube with a light and camera on the tip, which sends images of your oesophagus, stomach, and duodenum to a screen.

The endoscope is safe and will not interrupt your breathing. This is because it passes down your food pipe – not your windpipe.

The endoscope will carefully be advanced through your oesophagus and into your stomach and duodenum, transmitting real-time images to a monitor as it does. A small amount of air may be introduced into your stomach through the endoscope to inflate it and provide a clearer view of the stomach lining. This can cause you to burp and feel a little bloated.

If abnormalities are detected, your doctor may take a biopsy by using small instruments passed through the endoscope. This should be painless. Biopsies involve taking small tissue samples for further analysis in a laboratory. In some cases, therapeutic interventions, such as stopping any bleeding, can also be performed during the procedure.

Once the examination is complete, the tube will be withdrawn quickly and safely. The procedure will take between 15 – 45 minutes, depending on whether you have a treatment or biopsies are taken.


After the procedure, you will be taken by a specialist nurse to your room and our team will monitor your vital signs.

You will be given something to eat and drink when you feel ready. However if you had the local anaesthetic throat spray, you will need to wait for your swallow reflex to return to normal. This can take up to one hour.

Your doctor will explain the results of the gastroscopy and let you know if they took any biopsies or performed a treatment before you leave hospital.

If you had sedation, you should be picked up and looked after for the next 24 hours while it wears off. During this time do not drink alcohol, cook or make important decisions.

You may have a sore throat and a stomach ache after a gastroscopy. However, this should pass in a few hours.

If you had a biopsy, the results will be ready in one week, so you should book a follow-up appointment to discuss your results and possible treatments.

Hospital Fee Guaranteed


The price shown includes all costs associated with your treatment, from admission to discharge.

Doesn’t include surgeon or anaesthetist fee.

Our hospital fee is guaranteed at the price quoted and valid for one month from the date issued, subject to pre-assessment.

How to pay for your treatment

If you’re… paying for yourself

Did you know you don’t need private medical insurance to come to St John & St Elizabeth Hospital? As a self-pay patient, you can access safe, outstanding quality health care at times to suit you.

For scans and tests, as well as to see most consultants, you’ll still need to be referred by a medical professional like your GP, but as a self-pay patient, the process is more straightforward. You won’t need authorisation from an insurance provider, and you’ll have greater choice of consultant and appointment times.

If you’re… insured

St John & St Elizabeth Hospital is approved by all major medical insurance companies. If you have a personal private health insurance policy, or your company provide it for you, you can use it to pay for your care from your initial consultation through to treatment, surgery and aftercare such as physiotherapy. Not all private health insurance plans cover the same things. It’s very important to check exactly what you are covered for with your insurance provider.