Test and Treatment: Colonoscopy

In colonoscopy, a flexible tube called a colonoscope is used to view the colon to look for disorders such as polyps. The day before a colonoscopy, you will be given laxatives. You may also be given sedatives before the procedure, which takes 15–60 minutes and is usually painless. Instruments passed through the colonoscope can be used to take tissue samples or perform certain treatments. A similar viewing technique called sigmoidoscopy is used to examine the rectum and lower part of the colon.

During the procedure

The colonoscope is passed through the anus and rectum into the colon. Once the tube is inside, you will not feel it moving.


Intestinal polyp

An intestinal polyp attached to the wall of the colon can be seen in this view through a colonoscope. Small polyps can often be painlessly removed during the colonoscopy.

From the 2010 revision of the Complete Home Medical Guide © Dorling Kindersley Limited.

The subjects, conditions and treatments covered in this encyclopaedia are for information only and may not be covered by your insurance product should you make a claim.

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