A range of diagnostic techniques are used to determine the cause of your symptoms. These techniques are highly sophisticated and can accurately diagnose most gastroenterological conditions.

You will be given detailed information about whichever procedure you are having before you attend for your appointment.

The person carrying out the procedure will endeavour to put you at your ease and to answer any questions that you may have.

Although you may feel a little apprehensive about undergoing one of these investigations, please be assured they are routine procedures that should help to get to the bottom of whatever is causing your symptoms. This is the first step towards feeling better.


About Endoscopy

An endoscopy is a way to look inside your body using an instrument called an endoscope. This is a flexible tube with a light at the end of it and a camera.

The endoscope can be inserted through a natural opening in your body – down your throat or through your bottom.

Images of the inside of your body are relayed to a TV screen so the doctor can see what is going on inside you. They are used to investigate symptoms and perform certain types of surgery.

Common types of Endoscopy

In gastrointestinal conditions, the most common types of endoscopy are:

  • Gastroscopy (Upper gastrointestinal endoscopy)
  • Colonoscopy

No, you are likely to experience mild discomfort during an endoscopy but it will not be painful. You may be given a sedative to help you to relax and you may be given a local anaesthetic.

Rarely you can develop an infection in the part of the body that is being examined. This will be treated with antibiotics if it occurs. Another rare complication is perforation of an organ or excessive bleeding which may require surgery or a blood transfusion. Sometimes the medication used to sedate you may cause sickness, irregular heartbeat or breathing difficulties.

Yes, you will be able to go home once the effects of the sedative have worn off, although a friend or relative will need to take you home.

Upper gastrointestinal endoscopy


An upper gastrointestinal endoscopy – also called a gastroscopy – is used to look inside the oesophagus, stomach and the first part of the small intestine.

It is used to:

  • Investigate problems such as:
    • Difficulty swallowing.
    • Persistent abdominal pain.
  • Diagnose conditions such as:
    • Stomach ulcers.
    • Gastro-oesophageal reflux disease.
  • Treat certain conditions such as:
    • Bleeding ulcers
    • Polyps (cancerous or non-cancerous)

What to expect

A gastroscopy takes less than 15 minutes, although it may take longer if it is used to treat a condition. Your throat will be numbed with a local anaesthetic and you may choose to have a sedative, which will help to relax you although you will still be awake.

The doctor will place the endoscope in the back of your mouth and ask you to swallow the first part of the tube. This will be guided down your oesophagus and into your stomach.

The procedure can feel uncomfortable but is not painful. There is a small risk of internal bleeding or tearing to the oesophagus, stomach or duodenum.


You may experience a gagging sensation when the endoscope is inserted into your throat - this is reduced by spraying anaesthetic into your throat. You may develop a mild sore throat afterwards.

A gastroscopy is quick. The procedure takes approximately 15 minutes and you will need around half an hour to recover from the effects of sedation, if you received it. You will need someone to accompany you home if you were sedated.

Complications are rare with this procedure however they can occur. You may have a sore throat afterwards. Rarely there is a risk of more serious complications including bleeding, perforation, inhaling liquid into the lungs and an allergic reaction to any drugs administered.



A colonoscopy is used to examine your large bowel using a long, flexible tube called a colonoscope, which has a small camera and light at one end. The doctor will be able to see inside your bowel as images from the camera are relayed to a TV screen.

The device is used to take tissue samples called biopsies.

What to expect before, during and after

A colonoscopy takes around an hour. Your bowel needs to be empty for the procedure to be effective so you will be asked to eat a special diet and to take a laxative to empty your bowel the day before the procedure.

You will be given a sedative to help you to relax and the doctor will gently insert the colonoscope into your bottom and along your large bowel. You are likely to experience some discomfort although it isn’t painful.

The colonoscope has a light and a camera at one end, which sends images to a monitor. This enables the doctor to see clearly what is going on inside your bowel and identify what might be causing your symptoms. A biopsy might also be taken for analysis in the lab.

If you are an older person it is a good idea to have someone with you for 24 hours after a colonoscopy. You shouldn’t drive for 24 hours until the effects of the sedative have fully worn off.

Sometimes it is not possible to pass the colonoscope completely around the bowel. If this happens you may need to have a CT colonoscopy also known as a virtual colonoscopy.


A colonoscopy is a commonly used procedure and complications are rare. However, as with any medical procedure there are some small risks. Rarely you might experience bleeding, a tear in the bowel or infection. If these do occur they will be treated with antibiotics or surgery.

A colonoscopy is a highly effective way of detecting polyps in the colon or rectum, as well as other abnormalities. If left untreated, polyps can go on to develop into colorectal cancer so it is important to identify and treat them as early as possible.

You will be given detailed instructions by your doctor and it is important to follow these. Certain foods mimic the appearance of blood or abnormalities in the colon and should be avoided. It is important that the colon is empty to provide the best visibility during the colonoscopy. You should avoid eating the day before the procedure, as instructed on your appointment letter.

Experienced bowel doctor, here to help you

The sooner you seek help, the sooner your chances of returning to health and getting your life back on track.

There really is nothing to feel embarrassed about and everything to be gained by coming to talk to a specialist.

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