Gregory Endoscopy Centre

at Brigham and Women's Faulkner Hospital

Flexible Sigmoidoscopy

What is a flexible sigmoidoscopy?

A flexible sigmoidoscopy is a medical procedure to visually examine the rectum and the sigmoid colon (portion of the large intestine from the rectum to the last part of the colon) for abnormalities.

During the procedure, a thin, flexible, lighted tube, called a sigmoidoscope, is placed into the rectum and last part of the colon. The sigmoidoscope lets the doctor take pictures and look at the lining of the rectum and last part of the colon.

How should you prepare for a sigmoidoscopy?

After you schedule your appointment with us, you will be mailed complete instructions on how to prepare for your procedure. A printable PDF version is available here.

Here’s a synopsis of the key things that you should do to prepare:

  1. Call your insurance company and ask if the sigmoidoscopy test is covered for the reason given by your doctor.
  2. Ask your insurance company if you need a referral for the sigmoidoscopy. If they say “yes,” then you MUST get a referral from your primary care physician.
  3. Update your registration.
  4. If sedation is required, make plans for someone to come with you to the hospital.
  5. Five days prior to your procedure, please start a low-fiber diet and do not eat corn, raw vegetables or take fiber supplements (Metamucil®) or iron.
  6. If you take Coumadin®, Plavix® or other blood thinners, please talk to the doctor who prescribed it.
  7. If you are diabetic, please talk to your doctor about how to take your medication in order to prevent low blood sugar.
  8. Have a light breakfast and lunch the day before the exam.
  9. Please take one bottle of magnesium citrate at 4 pm on the day before your sigmoidoscopy. This is available without a prescription. Consume only clear liquids after the magnesium citrate. No solid food can be eaten until after the sigmoidoscopy is completed. Please use one FLEET® ENEMAS two hours before you leave for the hospital. FLEET is a brand of enema which is available in most pharmacies without a prescription.
What should you expect on the day of your sigmoidoscopy procedure?

After you check in, one of our nurses will meet with you to review your medical problems and medications. You will proceed to our procedure room where your blood pressure, pulse and oxygen level will be carefully monitored. Usually an IV will be placed for fluids or meds. The test itself usually takes less than half an hour. Before leaving, our staff will talk to you about your test and will let you know when you can go back to eating your regular diet.

The sigmoidoscopy is usually done without the conscious sedation. However, if your physician indicates that you will require sedation during the procedure, please discuss it with your medical provider prior to the test date. Please also note that if your procedure requires sedation, you will need to arrange for someone to drive you home.


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