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Doctor and technician performing colonoscopy on patient lying on side.

Sigmoidoscopy is a procedure used to look at the lower colon and rectum. This test can help find the source of belly pain, rectal bleeding, and changes in bowel habits. Sigmoidoscopy is also used as part of the screening for colorectal cancer. It is done using a sigmoidoscope. This is a flexible tube with a viewing lens and light.

The U.S. Preventive Services Task Force recommends screening for colorectal cancer in adults ages 50 through 75 at recommended intervals. Your healthcare provider may also recommend other colon cancer screening methods such as colonoscopy. Talk with your healthcare provider about colorectal screening. If a sigmoidoscopy shows polyps, you may need a colonoscopy as the next step.

Getting ready

Here is how to get ready for the test:

  • Tell your healthcare provider about any medicines you take. Also tell your provider about any health conditions you may have.

  • Ask your healthcare provider about the risks of the test. These include bleeding and bowel puncture.

  • Your rectum and colon must be empty for the test. Follow the diet and bowel prep instructions. Otherwise the test may need to be rescheduled.

During the test

Here is what to expect:

  • The test is done in the healthcare provider’s office or in a hospital. You may wear a gown or a drape over your lower body.

  • The procedure usually takes 10 to 20 minutes.

  • The healthcare provider does a digital rectal exam to check for anal and rectal problems. The rectum is lubricated and the scope put in.

  • You may have a feeling similar to needing to have a bowel movement. You may also feel pressure when air is pumped into the colon This is done so that the healthcare provider can get a better view. It’s expected that you will pass gas during the procedure.

After the test

Here is what to expect:

  • Usually you’ll discuss the results with your healthcare provider right away, unless you’re having other tests.

  • If tissue samples (biopsies) were taken, ask when to call for the results. 

  • Try to pass all the gas right after the test. Otherwise you may have bloating and cramping.

  • After the test you can go back to your normal eating and other activities.

When to call your healthcare provider

Call if you have any of the following after the procedure:

  • Pain in your belly

  • Fever

  • Dizziness or weakness

  • Extra rectal bleeding. Slight bleeding or spotting is normal, especially if a biopsy was taken.

Author: StayWell Custom Communications
Last Annual Review Date: 7/1/2019
Copyright © The StayWell Company, LLC. except where otherwise noted.
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