You should consider getting a colonoscopy starting at age 45 if you are at average risk for colorectal cancer. Screening usually continues through age 75, while decisions from age 76 to 85 depend on your health, past screening history, and personal preferences.
A colonoscopy may be needed earlier or more often if you have a higher risk. This includes a strong family history of colorectal cancer, previous polyps, inflammatory bowel disease, certain inherited syndromes, or past radiation to the abdomen or pelvis.
A colonoscopy is also used after an abnormal stool test, such as a positive FIT, to check for the cause. If the bowel was not cleaned well enough during a prior colonoscopy, the test may need to be repeated sooner because the doctor may not have been able to see the colon clearly.
For average-risk adults, colonoscopy is often done every 10 years when results are normal. Talk with a primary care doctor or gastroenterologist about the best timing for you, especially if you have symptoms, risk factors, or a family history of colorectal cancer.