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What is IBD?

IBD stands for Inflammatory Bowel Disease. The two most common forms are Crohn's Disease (often just called Crohn's) and Ulcerative Colitis (UC).

In both UC and Crohn's parts of the digestive system (the gut), which includes the intestines or 'bowels', become sore and inflamed. Crohn's can affect any part of the digestive system from the mouth to the anus. UC affects the colon (large intestine) and rectum.

Information Sheets and Booklets:

What are the main symptoms of IBD?

IBD symptoms vary from person to person - and usually over time. IBD is a chronic (long term) disease and if you have IBD you will probably have periods of good health (remission) and then relapses or 'flare-ups' when the symptoms get worse.

The main symptoms are:

  • abdominal pain
  • diarrhoea (sometimes mixed with blood, especially in Ulcerative Colitis)
  • tiredness and fatigue
  • loss of appetite
  • weight loss
  • abscesses and fistulas (in Crohn's)
  • swollen joints, mouth ulcers and eye problems

Who gets IBD?

Anyone can develop IBD - and at least 261,000* people are affected by Ulcerative Colitis (146,000*) and Crohn's Disease (115,000*) in the UK - Although recently published data suggest that this could be as many as 620,000.

The illnesses can occur at any age, but often begin in younger people aged 10-40. Both conditions are found worldwide, but are more common in developed countries.

*Figures published by NICE (2012 and 2013)

What causes IBD and is there a cure?

Nobody is sure, but researchers and experts think both Crohn's and UC are caused by a combination of factors, including:

  • the genes you are born with
  • an abnormal reaction of the digestive system to bacteria in the intestine
  • an unknown 'trigger' or set of triggers that could include viruses, other bacteria, diet, stress, or something else in the environment.

There isn't a cure at the moment but a lot can be done with medication and surgery to help keep symptoms under control and to reduce the chance of a flare-up.

What about Microscopic Colitis?

Microcopic Colitis is a less well known form of inflammatory bowel disease - and is not usually included under the term 'IBD'. It is called Microscopic Colitis because the inflammation can only be seen under a microscope. Its main symptom is watery diarrhoea, and it is becoming increasingly common. Our information sheet Microscopic Colitis gives more details.

Content based on Understanding IBD - June 2014. Next planned review 2016

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