Colonoscopy may be recommended if the patient has symptoms suggesting possible problems in the colon or rectum. These
symptoms include bleeding, change in bowel habits and other unexplained abdominal symptoms. Colonoscopy is also useful
in monitoring patients with inflammatory bowel disease, and for follow-up of patients with history of colon cancer or
polyp.
For colonoscopy and all other forms of examination of the colon, it is important to clear the colon of stools. Patients
are asked to take very potent laxatives to clear the colon. In most cases, if the procedure is to be done in the
morning, the patient will be asked to take the laxatives and purge the night before. If the procedure is to be done in
the afternoon, it will be advisable to clear the bowels in the morning on the day of examination. Many patients have
expressed that the preparation is the worst part of the entire procedure, since it is common to have to make multiple
trips to the toilet after taking the medications to clean the colon. To prevent dehydration, patients are encouraged to
drink as much fluids as possible while on laxatives in preparation for colonoscopy. Consumption of foods high in fibre,
such as fruits and vegetables, is discouraged 2 days prior to examination. For patients who are on aspirin or other
blood-thinning medications, the doctor will give appropriate advice on when those medications should be stopped.
On the day of examination, it is important that the patient remains calm and relaxed. Most people are fearful of
colonoscopy because they feel that it is a very invasive procedure and are concerned about pain. However, most patients
do not feel any pain or even remember about the procedure after they wake up from sedation. It is also advisable to
reach the Endoscopy Centre about 30 minutes to an hour ahead of the time of appointment in case a final trip to the
toilet is required.
Once inside the examination room, the doctor will likely administer a sedative by injection, though some patients may
want to watch the procedure “live” and want to go through the entire procedure awake. This is possible as the procedure
makes most people feel bloated and have the urge to pass motion rather than actual pain.
Most people do not have any side effects after the procedure. Some people may feel bloated because of residual air left
in the colon. Do remember that it is normal to have less bowel movement in the few days following the procedure because
a lot of stools have already been cleared out by the bowel preparation.
Colonoscopy is a generally safe investigative procedure when performed by a trained specialist. Current national
guidelines recommend screening from the age of 50 years for early detection of colon cancer. However, it is known that
colon cancer has a long pre-cancerous phase where it stays as a benign polyp (protuberance) for a number of years before
turning cancerous. As such, screening to detect and remove polyps at an earlier age may actually prevent cancer instead
of detecting early cancer which still requires surgery. Early detection of bowel malignancy is always beneficial, as it
is the only proven way to improve prognosis and survival rates of cancer patients.