When Your Child Needs a Colonoscopy or Sigmoidoscopy

A colonoscopy is a test that lets the doctor look inside your child's colon and rectum. A sigmoidoscopy is a shorter form of this test that only looks at the lower part of the colon (the sigmoid colon) and the rectum. The provider may take tissue samples (biopsy). They may also check for growths (polyps) or bleeding. How long the test will take depends on how clean the colon is, what the health problem is, and if treatment is needed. Colonoscopy usually takes about 45 minutes. Sigmoidoscopy usually takes about 10 to 15 minutes.

Before the test

Your child’s colon may need to be cleaned out before the test. Follow any instructions that your child's provider gives you. You may need to:

  • Have your child drink a liquid bowel prep before the test

  • Switch your child to a clear liquid diet 1 or 2 days before the test

  • Give your child a laxative or suppository the night before and on the day of the test, as the clinic instructs

Let the doctor know

For your child’s safety, let the healthcare provider know if your child has:

  • Allergies to any medicine, sedative, or anesthesia

  • Heart or lung problems

  • Takes any medicines, especially aspirin

During the test

A colonoscopy or sigmoidoscopy is done by a doctor in an ambulatory surgery center.
  • Your child lies on an exam table on their side or back.

  • Your child may be given a medicine that makes them sleepy (a sedative). Or your child is given medicine that makes your child sleep (anesthesia) by facemask or IV. A trained nurse or anesthesiologist helps with this process and also monitors your child during the procedure. They use special equipment to check your child’s heart rate, blood pressure, and blood oxygen levels.

  • The doctor inserts a colonoscope or sigmoidoscope into your child’s rectum and colon. This is a long, flexible tube with a camera and a light at the end. During a sigmoidoscopy, the scope will only move up through the sigmoid colon.

  • Air is pushed through the scope to expand your child’s lower GI tract. Water may also be used to clean the colon.

  • Images of your child’s colon are viewed on a screen as the scope moves along.

  • The doctor may take tissue samples and remove any polyps that are found.

After the test

When the test is done, your child can expect the following:

  • Your child will be moved to a recovery room. It may take 1 to 2 hours for the sedative to wear off.

  • Your child can return to their normal routine and diet right away, unless told otherwise.

  • The doctor may discuss early results with you after the test. You will receive complete results when they are complete, usually in 2 to 3 weeks.

Helping your child get ready

You can help your child by preparing in advance. How you do this depends on your child’s needs. Try the following:

  • Explain that the healthcare provider will be testing the colon and rectum. Use brief and simple terms to describe the test. Younger children have shorter attention spans, so do this shortly before the test. Older children can be given more time to understand the test. 

  • As best you can, describe how the test will feel. Your child won’t feel anything once the medicines take effect.

  • Allow your child to ask questions.

  • Use play if it helps. This can involve role-playing with a child’s favorite toy or object. It may help older children to see pictures of what happens during the test. 

When to call your child's provider

Call the provider if your child has any of the following:

  • Abdominal pain, nausea, or vomiting

  • More than a tablespoon of blood in the stool right after the test or blood in the stool for several days

  • A fever over 100.4°F (38.0°C) that won't go away, or other fever that the provider has told you to call them about

© 2000-2024 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.