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Surgical Services


IntroductionShow [+]Hide [-]

What is a colonoscopy?

  • It is an examination of your large bowel (colon).
  • It is performed using a colonoscope (a flexible tube, with a small camera at one end) which is passed carefully through your back passage (anus), and air is inflated into the bowel. 
  • The colonoscope is then advanced around the large bowel enabling the endoscopist to look directly at its lining.

Colonoscopy Diagram

Alternative Tests:

Although there are alternatives your doctor has decided that this is the best test for you.

One alternative is a barium enema x-ray examination. It is not as informative as a colonoscopy and has the added disadvantage that tissue samples cannot be taken.

If you want further information, please discuss this with your GP or the doctor who has referred you for this test.

What are the risks of having a colonoscopy?

A colonoscopy carries a small risk of complications, the main risks are: 

  • Perforation or tear of the lining of the bowel wall (1 in every 1000). An operation is nearly always required to repair the hole. The risk of perforation is higher with polyp removal.
  • Bleeding may occur at the biopsy site or polyp removal (1 in every 100-200). This may stop on its own but may require further treatment and an operation may be required.
  • A reaction to drugs used during the test may require you to stay in hospital.

Before your procedureShow [+]Hide [-]

How do I prepare for the colonoscopy?

If you require ambulance transport, please arrange this with your GP at least seven days before your appointment.

If you are a Diabetic or taking Warfarin, Aspirin or Clopidogrel tablets, please contact the Endoscopy Unit.

To give the endoscopist a clear view of your bowel you should stop iron preparations and bulking agents (bran, Fybogel, Regulan) for one week before the test.

All other medication should be taken as normal.

The day before the colonoscopy:

It is extremely important that the bowel is clean during your test so you must drink as much clear fluid as possible. 

Please follow the instructions carefully and take the enclosed bowel preparation as directed. 

Be prepared for frequent bowel actions starting within three hours of taking the laxatives and make arrangements to be near toilet facilities.

Aim to drink at least one full tumbler of clear liquid per hour to avoid becoming dehydrated. 

The day of the colonoscopy:

Please continue to drink clear fluids up to two hours before your appointment time.

Please bring your dressing gown and slippers with you.

Freeman Hospital appointments

Please report to the Admission Desk (Main Entrance) and then go to the Day Treatment Centre (Ward 21) Level 3. 

RVI appointments

Please report to Ward 39 (Gastroenterology Unit), Leazes Wing. 

NGH appointments

Please report to Ward 19, Endoscopy Unit.

In all Hospitals

  • Before the procedure you will be seen by a qualified nurse and the Endoscopist and you will have the opportunity to discuss any problems or worries. 
  • You will be asked to sign a consent form indicating that you understand the nature and risks of the procedure. The consent form is a legal document, therefore please read it carefully.
  • Please leave any valuables at home.

During your procedure Show [+]Hide [-]

What will happen during the colonoscopy?

  • Your test will be performed by a qualified endoscopist or a trainee endoscopist under direct supervision.
  • Before the colonoscopy you will be asked to change into a hospital gown. 
  • A clip will be lightly attached to your finger to check your pulse rate and level of oxygen and your blood pressure may also be monitored.
  • Oxygen will be administered into your nostril.
  • You will be asked to lie on your left side and then be given an injection to make you relaxed and sleepy. This is not a general anaesthetic and you will not be unconscious, but it is unlikely that you will remember much about the procedure.
  • When the colonoscope is inserted into your bottom, air is gently passed into the bowel. This opens up the bowel so the endoscopist can see where they are going. At first you may feel that you want to go to the toilet. You may feel a little embarrassed that you will pass a motion. Do not worry! It is the air that causes this feeling. You will not soil yourself.
  • Throughout the test the endoscopist will put air into your bowel to provide a clear view. This may result in some mild discomfort.
  • Small tissue samples (biopsies) can be taken through the colonoscope, which is painless. These will be retained.
  • If a polyp, a small growth on the wall of the bowel is found, then it may be removed. A polyp is a protrusion from the lining of the bowel. Polyps when found are generally removed or sampled by the endoscopist as they may grow and later cause problems.
  • You may require Argon Plasma Coagulation Treatment. This involves the use of a jet of argon gas that is directed through a probe which is passed through the colonoscope. It is used to destroy abnormal tissue and /or to seal off bleeding blood vessels.
  • A video recording and /or photographs may be taken for your records and will only be seen by those involved in your care.
  • The colonoscopy will take 20 to 40 minutes.

After your procedureShow [+]Hide [-]

What will happen after the colonoscopy?

  • You will be allowed to rest quietly in the recovery area where a qualified nurse will observe you until the main effects of the injection have worn off. 
  • You may feel a little bloated but this will settle quickly. 
  • Please arrange for a relative or friend to collect you directly from the ward to take you home after your colonoscopy. Please liaise with the ward staff to arrange collection time. You will not be fit to go home by public transport. 
  • Once home you should rest quietly for the remainder of the day.

Please ensure a responsible adult remains with you until the next morning as the after effects of the injection make you sleepy or forgetful for 24 hours after the test.

For 24 hours following the test you must not:

  • Drive a vehicle
  • Operate machinery
  • Drink alcohol
  • Sign any legal documents
  • Be left alone to care for children

When will I know the result of my colonoscopy?

  • Sedation makes you forgetful, but the endoscopist or nurse, in the presence of your accompanying relative or friend, will discuss the results of the test with you, if you wish.
  • If you have had biopsies taken you will receive the results at your out patient appointment.
  • A full report will be sent to your doctor. 
  • Before you are discharged you should be given clear details concerning follow-up arrangements.

Questions or problems?Show [+]Hide [-]

If you have any further questions you should contact:

Freeman Hospital:

  • Endoscopy Unit (between 09.00 - 16.30) - 0191 223 1208
  • Day Treatment Centre (Ward 21) - 0191 223 1294


  • Endoscopy Unit between 9.00 am - 4.30 pm - 0191 282 5655

If you have any queries or require any further information out of these hours, please contact your GP, visit NHS Emergency and Urgent Care Services or call tel: 111. 

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