What is a colonoscopy?

A colonoscopy is an outpatient procedure that is done to examine the inside of the large intestine (colon and rectum). The examination uses an instrument called a colonoscope (sometimes called a scope). This flexible instrument, is very long and includes a camera and the ability to remove tissue (you do not feel tissue being removed). A colonoscopy is commonly used to evaluate gastrointestinal symptoms, such as bleeding, abdominal pain or changes in bowel habits (how often you poop, how easily you poop, and the color and consistency of your poop).

Colonoscopy can be used to detect ulcerative colitits, polyps, cancer, diverticulosis and Crohn's disease.

A colonoscopy can be used to detect many different types of conditions.

Some people may avoid the procedure due to embarrassment or a reluctance to do the preparation. There are many bowel preparations available, and they come in different sizes and tastes. Also, the colonoscopy team respects your privacy during the entire procedure. Colonoscopies are done to check for colorectal polyps or cancer. Removing polyps early means they can’t turn into cancer.

The medical community recommends that anyone who does not have risk factors for colorectal cancer should get a screening colonoscopy starting at age 50. The American Cancer Society has recommended that the screening start at age 45, and the Multi Society Task Force recommends that African Americans start screening at 45 (this is due to an increased risk of cancer). The timing of your colonoscopies varies depending on the findings of your test. You may need to have a colonoscopy at a younger age if you have an increased risk of colon cancer. These risk factors can include:

  • Having familial polyposis syndrome (a condition that runs in your family and is linked to an increased risk of forming polyps).
  • Having a genetic condition associated with colon cancer.
  • Having inflammatory bowel disease, such as Crohn’s disease and ulcerative colitis.
  • Having first-degree relatives with colon cancer (that is, your mother or father, brother or sister, or child).
  • Having multiple relatives with colon cancer.

Last reviewed by a Cleveland Clinic medical professional on 10/27/2019.


  • Expert knowledge and experience of healthcare providers at Cleveland Clinic.
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