During a flexible sigmoidoscopy, a healthcare provider uses a scope to view the inside of the lower (sigmoid) colon and rectum. The procedure helps diagnose bowel problems, such as ulcerative colitis, an inflammatory bowel disease (IBD). It can also detect colon polyps that can become colon cancer.
A gastroenterologist, or healthcare provider specializing in the gastrointestinal system, performs a flexible sigmoidoscopy to view the inside of the lower (sigmoid) part of your colon and rectum. Your healthcare provider uses a sigmoidoscope, a flexible lighted tube with a camera. The procedure helps your healthcare provider diagnose, and sometimes treat, bowel disorders and cancer.
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Your healthcare provider may recommend a flexible sigmoidoscopy if you experience:
Healthcare providers use flexible sigmoidoscopies to diagnose:
Both procedures are screening tools for colon cancer. A sigmoidoscopy is less invasive. It allows your healthcare provider to see only the lower part of the colon. With a colonoscopy, your healthcare provider can examine all of the large intestine. If the flexible sigmoidoscopy procedure reveals polyps in your lower colon, your healthcare provider can remove them. You’ll need a colonoscopy next. During a colonoscopy, your healthcare provider can remove additional polyps before they turn cancerous.
Your bowels (stomach and intestines) must be completely empty before this examination. Your healthcare provider might have you use an enema in the office just before the procedure, or they’ll have you do the following at home:
Note that your own healthcare provider’s office might have different instructions for you to follow.
A flexible sigmoidoscopy takes place as an outpatient procedure at your healthcare provider’s office or medical center. You can go home the same day. Because flexible sigmoidoscopy isn’t as involved as a colonoscopy, you shouldn’t need medicine that puts you to sleep (anesthesia). The procedure may feel a bit uncomfortable, but it’s usually done in less than 30 minutes.
You’ll lie on your left side on an exam table. During the procedure, your healthcare provider:
You may have belly pain, bloating or cramps for an hour or so after the procedure. You should feel better after you pass gas. If your provider removed polyps or tissue, you may have some light rectal bleeding. You should be able to resume activities and a normal diet after the procedure.
Potential complications of a flexible sigmoidoscopy are rare but include:
Diagnostic results may be available immediately at your provider’s office. Often, providers send biopsy (tissue) samples to a lab. It can take up to two weeks to get biopsy results.
You should call your healthcare provider if you experience:
Last reviewed by a Cleveland Clinic medical professional on 10/19/2020.
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