Upper GI


Gastroscopy is a diagnostic test that enables the doctor to look inside your oesophagus (the pipe that leads to the stomach), the stomach, and the duodenum (small intestine). The gastroscope is very thin – typically around 9mm in diameter – and is passed into the stomach through the mouth. Your doctor is then able to visualise your oesophagus (the pipe that leads to the stomach), your stomach, and the top part of your duodenum, or small intestine. The images are magnified many times and viewed on a video screen. It is considered a very safe and precise way of investigating the upper gastro-intestinal tract.

What happens


The patient is kept nil by mouth that is, told not to eat or drink, for at least 4-6 hours before the procedure. Any heart or blood pressure medication can be taken with a sip of water.


You will be given a sedative to help you to relax. This is usually given by an injection into a vein in the back of your hand. The sedative can make you drowsy, but it does not a general anaesthetic.

You lie on your side. You are asked to put a plastic mouth guard between your teeth. This protects your teeth and stops you biting the endoscope. Modern endoscopes are quite thin and easy to swallow. The doctor then gently pushes it down your oesophagus and into your stomach and duodenum.

The video camera at the tip of the endoscope sends pictures to a screen. The doctor watches the screen for abnormalities of the oesophagus, stomach and duodenum. Air is passed down a channel in the endoscope into the stomach to make the stomach lining easier to see. This may cause you to feel “full” and want to belch.

The doctor may take one or more biopsies of parts of the inside lining of the gut – depending on why the test is done and what they see. This is painless. The biopsy samples are sent to the lab for testing, and to look at under the microscope. The endoscope is then gently pulled out.

How Long Does It Take?

A gastroscopy usually takes about 10 minutes. However, you should allow at least 2 hours for the whole appointment to prepare, give time for the sedative to work (if you have one), for the gastroscopy itself, and to recover.

After the procedure, some recovery time is usually allowed to let the sedative wear off. Outpatient recovery time can take an estimate of 30-60 minutes. You will require someone to help you home afterwards. You will not be able to drive or operate any machinery for at least 12 hours or as otherwise directed by the anaesthetist.You will need to go home and rest for the remainder of the day.