At What Age Should I Have a Colonoscopy?

The age at which you should have your first colonoscopy varies according to your level of risk for developing colon cancer. Guidelines developed collaboratively by the American Cancer Society, the American College of Radiology and the U .S. Multi-Society Task Force on Colorectal Cancer give recommendations for three risk levels.

Levels of Risk

You are at average risk of developing colon cancer if you have no other risk factors besides age. You have an increased risk if you have one or more immediate family members who have had colon cancer. You are at high risk if you have an inflammatory bowel disease such as ulcerative colitis or Crohns disease, or if you have a family history of certain colorectal cancer syndromes. The risk levels help determine when to get a colonoscopy.

Average Risk

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Persons of average risk should undergo some type of colon cancer screening at age 50. Although there are other options, a colonoscopy is the most thorough screening test available.

Increased Risk

Persons who are at an increased risk should have a colonoscopy at age 40. If a family member was younger than age 50 when diagnosed with colon cancer, you should have the colonoscopy 10 years earlier than the age of that person when diagnosed. Colon cancer treatment is better tolerated by younger and/or healthy patients.

High Risk

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The recommended age for a colonoscopy for people in this category is sometimes as young as 20 to 25 years. People at high risk for colon cancer are normally under the care of a specialist who makes the recommendation for a colonoscopy on the basis of careful monitoring and observation. For high risk patients, early detection makes a big difference in the success of colon cancer treatment.


The American Cancer Society warns that these colonoscopy guidelines should be used as a starting point for discussions with your doctor about your particular situation. Each case is different, and no set of recommendations is right for every individual.