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7th December, 20201 min read

Toxic Megacolon

Medical reviewer: Dr Ann Nainan
Author: Dr Lauretta Ihonor
Last reviewed: 01/12/2020
Medically reviewed

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Toxic megacolon is a potentially life-threatening condition in which the large bowel becomes wider than normal. It’s usually a complication of bowel inflammation or infection.

Really bad bloody diarrhoea is the most common symptom of toxic megacolon, but it can also cause:

  • tummy pain and tenderness
  • tummy swelling
  • fever and chills

How is toxic megacolon diagnosed?

A doctor may suspect you have toxic megacolon based on your symptoms and medical history, but they will usually also look at and feel your tummy.

You will probably need other tests to confirm the diagnosis. These include:

What is the treatment for toxic megacolon?

Toxic megacolon is a potentially life-threatening condition that needs emergency treatment in hospital. You may be given fluids, antibiotics and/or steroids through a vein in your arm (IV). In some cases, you may also need surgery.


  1. Toxic colitis and toxic megacolon - Symptoms, diagnosis and treatment | BMJ Best Practice [Internet]. 2020 [cited 3 December 2020]. Available here.
  2. UpToDate [Internet]. 2020 [cited 3 December 2020]. Available here.
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