A flexible sigmoidoscopy is a visual exam of the rectum and lower portion of the colon (large intestine). The exam is done with a tool called a flexible sigmoidoscope. The sigmoidoscope is a flexible tube with a tiny camera on the end. This instrument allows the doctor to see inside your rectum and colon.


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Reasons for Procedure

It is used to examine and diagnose problems inside your rectum and lower colon. The procedure is most often done to:

  • Obtain tissue samples for testing
  • Identify the cause of rectal bleeding, diarrhea, constipation, lower abdominal pain, or inflammation
  • Detect the presence of or remove polyps]]> (small growths than can turn cancerous)
  • Monitor response to treatment if you have ]]>inflammatory bowel disease]]>
  • Screen for ]]>colorectal cancer]]>


Possible Complications

Complications are rare, but no procedure is completely free of risk. If you are planning to have a sigmoidoscopy, your doctor will review a list of possible complications, which may include:

  • Bleeding
  • Perforation or puncture of the bowel wall

Factors that may increase the risk of complications include:

  • Pre-existing heart or kidney condition
  • Treatment with certain medicines, including aspirin and other drugs with anticoagulant or blood-thinning properties
  • Prior abdominal surgery or radiation treatments]]>


What to Expect

Prior to Procedure

Talk to your doctor about your medicines. You may be asked to stop taking some medicines up to one week before the procedure, like:

  • Anti-inflammatory drugs (eg, aspirin]]> )
  • Blood thinners, like ]]>clopidogrel]]> (Plavix) or ]]>warfarin]]> (Coumadin)
  • Iron supplements or vitamins containing iron.

Your lower intestine must be completely cleaned out before the procedure. Any stool left in the intestine will block the view. This preparation may start several days before the procedure. Follow your doctor's instructions, which may include any of the following cleansing methods:

  • ]]>Enemas]]> —This fluid is introduced into the rectum to stimulate a bowel movement.
  • Laxatives—These medicines cause you to have soft bowel movements.
  • Drink a clear-liquid diet.
  • Oral cathartic medicines—You may be given a large container of fluid to drink, which will stimulate a bowel movement.
  • The night before, eat a light meal. Do not eat or drink anything after midnight.
  • Wear comfortable clothing.

Your doctor will likely do the following before the procedure:

  • Physical and rectal exam
  • Health history
  • Review your medicines
  • Test to check for hidden blood in your stool called ]]>occult blood]]>


Your doctor may sedate you to decrease discomfort.

Description of the Procedure

You will be positioned either on your left side with knees bent and drawn up toward your chest, on your back with your feet in stirrups, or on a special table. Try to relax, and breathe slowly and deeply. The doctor will do a rectal exam with his finger first. Then, the lubricated sigmoidoscope will be slowly inserted into your rectum. The scope is about the same thickness as a human finger. The scope will be passed through the rectum and into the colon. It will inject air into the colon to widen the passage and make it easier to see the walls.

The scope will provide a video of the colon lining as it moves along. The doctor will watch the video images to look for any abnormalities. A tissue sample and/or polyps may be removed.

How Long Will It Take?

The procedure typically lasts about 20–30 minutes.

Will It Hurt?

Most people report some discomfort when the instrument is inserted. You may feel cramping, muscle spasms, or lower abdominal pain during the procedure. You may also feel the urge to move your bowels. Tell the doctor if you feel any severe pain.

After the procedure, gas pains and cramping are common. These pains should go away with the passing of gas.

Postoperative Care

If any tissue was removed:

  • It will be sent to a lab to be examined. It may take 1-2 weeks for results.
  • A small amount of bleeding may occur during the first few days after the procedure.

The doctor will usually give an initial report after the scope is removed. Other tests may be recommended.

Be sure to follow your doctor's instructions, which may include:

  • Resume medicines as instructed by your doctor.
  • Resume normal diet, unless directed otherwise by your doctor.
Ask your doctor when you will be able to return to work. Also, do not drive until your doctor tells you that it is safe.

Call Your Doctor

After arriving home, contact your doctor if any of the following occurs:

  • Bleeding from your rectum—Notify your doctor if you pass a teaspoonful of blood or more.
  • Black, tarry stools
  • Severe abdominal pain
  • Hard, swollen abdomen
  • Signs of infection, including fever or chills
  • Nausea and vomiting
  • Inability to pass gas or stool
  • Chest pain or trouble breathing
In case of an emergency, call 911 .