What Is a Colonoscopy?

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A colonoscopy is a semi-invasive procedure performed with sedation, in which a physician, visually examines a patient's colon and, if necessary, removes polyps  or performs biospies. A physician may order a colonoscopy if a patient is experiencing gastrointestinal problems or symptoms. Additionally, many physicians recommend an annual colonoscopy for patients over 50 as a screening for colorectal cancer.

Typically, a Gastroenterologist, or a physician who specializes in the gastrointestinal system, performs a colonoscopy. The procedure itself involves a special scope, which is run through the rectum and into the colon, or large intestine. The video images picked up by the scope are transmitted to a screen, allowing the physician to detect any abnormalities indicating a disease or disorder. Common problems detected by colonoscopy include colon cancer, polyps, ulcerative colitis, Crohn’s disease and irritable bowel syndrome.

A colonoscopy is performed in a clinical setting on an outpatient basis. The patient must prepare for a colonoscopy by following a specific set of directions provided by their physician in advance. These directions are available on this website. Preparation for a colonoscopy involves cleaning out the intestines in order to optimize viewing. Most patients are advised to follow a clear liquid diet for 24 hours prior to their scheduled procedure and to “clean out” their bowels with a laxative the day before the colonoscopy. Physicians strongly emphasize following preparation instructions carefully, because failure to do so can cause results to be inaccurate or the entire procedure to be unsuccessful. Cancer can be missed is the bowel is not properly cleaned.

Medicines, you can take most prescription and non-prescription medicines the day before and the day of the colonoscopy. Your doctor should tell you what medicines to stop.

Medicines, if you have had a heart attack or stroke, it is important to continue your medications for these problems before the procedure unless otherwise instructed by Dr. Bray. These include Aspirin, Coumadin®/Warfarin, Plavix®/Clopidogrel and Xarelto®/Rivaroxaban. If you are on Coumadin®/Warfarin you will need a STAT INR 3-4 days prior to the colonoscopy.

If you have NOT had a heart attack or stroke and are on Aspirin, eg: are taking it preventatively, please stop the Aspirin 7 days prior to your colonoscopy unless otherwise instructed by your doctor.

When a patient arrives for a colonoscopy, he or she is provided with a gown and an intravenous (IV) is started. The IV will be used to give sedation during the test. Many people sleep during the test, while others are very relaxed, comfortable, and generally not aware. Different physicians use different forms of anaesthesia; their goal is to relieve apprehension and prevent pain or discomfort during the procedure.

The entire procedure from start to finish typically takes only a couple of hours—the colonoscopy itself takes only 10–20 minutes, but you will need time in the recovery room after the procedure for the sedation to wear off.  Even though a colonoscopy is an outpatient procedure, the patient will need transportation home afterwards because of the anaesthesia. It is illegal to drive for 24 hours in Quebec and Ontario after a colonoscopy. Post-procedure care will be provided by the facility and most people return to their normal diet within twelve hours following a colonoscopy.

 The majority of patients do not report any severe complications after a colonoscopy, but occasionally bleeding or a perforation (a small hole in the bowel) can occur. This is rare and the bleeding occurs in the first couple of weeks after the removal of a polyp, because this is the time when this area where the polyp was removed is healing. More than 50% of these individuals are on Aspirin or anti-inflammatories.   If you do not have a good medical reason to be on these medications, your Gastroenterologist will recommend you do not take these medications for a few weeks.   If you have a good medical indication, such as a previous heart attack or stroke, it will be recommended that you continue these medications

If you have significant bleeding (more than a cup) in the first few weeks after having a polyp removed, you should go to the nearest Emergency Room immediately.

Rarely a small hole in the bowel or perforation can occur. This is unlikely to happen, but if you develop significant abdominal pain later on in the day, you should go to the nearest Emergency Room to have this addressed.