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Medically reviewed by Last updated on Aug 31, 2022.

What is megacolon?

Megacolon is the stretching and widening of your colon. Bowel movements build up in your colon instead of passing through to your rectum. Megacolon can be caused by a genetic condition. You may be born without the nerves in your colon that give you the urge to have a bowel movement. Megacolon can also be caused by long-term constipation.

What are the symptoms of megacolon?

  • Abdominal bloating and pain
  • Nausea
  • Long-term or severe constipation
  • Pain or pressure at your rectum

How is megacolon diagnosed and treated?

Your healthcare provider will ask how often you have a bowel movement. Tell your provider if you strain when you have a bowel movement or have a history of constipation. Tell your provider the names of any medicines you take. Your provider may do a test to check if the muscles in your rectum are working properly. You may need a CT scan or x-ray. You may be given an enema with contrast solution to help your healthcare provider see your colon better. Your healthcare provider may remove a piece of tissue from your colon and test it. Megacolon is treated with surgery to remove the part of your colon that is not working properly.

When should I seek immediate care?

  • You have vomiting and fever.
  • You have severe diarrhea.
  • You have rectal bleeding or see blood in your bowel movements.

When should I call my doctor?

  • You continue to have symptoms after treatment.
  • You have questions or concerns about your condition and care.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

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Learn more about Megacolon

Treatment options

Symptoms and treatments

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.