Examination of the large intestine, the lower segments of the small intestine, the rectum and anus to identify and treat conditions of these organs.


Colonoscopy makes it possible to examine the large intestine, the lower segments of the small intestine, the rectum and anus. The gastroenterologist can thus identify and sometimes even treat conditions of these organs or monitor the development of known conditions.

The examination is carried out with the aid of a narrow, flexible tube (endoscope) fitted with a light source and a camera. This enables the gastroenterologist to examine the mucous membranes of the intestine and look for diseases. If changes are found, the doctor can take tissue samples (biopsies) for analysis under the microscope.

To provide a better view of the intestinal wall, the intestine is inflated during the examination. It is sometimes necessary to apply pressure to the abdomen in order to move the endoscope.

During the examination, the gastroenterologist is assisted by a nurse who has undergone specialist training. A colonoscopy can sometimes be painful. This is why you will generally be given medication during this examination.   

Preparation before the examination

Colonoscopy requires a thorough enema of the intestine beforehand as well as a special diet (eliminating dietary fibre) in the 3 days preceding the examination. Your doctor will give you instructions to follow precisely.

After the examination

If you have been given an injection of medications for the colonoscopy, you will be monitored until you wake up. In the hours following the examination, you may feel pressure in your abdomen (air in the intestines). If this feeling intensifies or you have a new stomach ache, if you experience bleeding from the anus or you have a fever, contact the centre immediately or go to the emergency department.