What are the symptoms?

Crohn’s Disease and Ulcerative Colitis are chronic (ongoing and life-long) conditions in which symptoms vary from person to person and will range from mild to severe. 

Symptoms  may also change over time, with periods of good health when you have few or no symptoms (remission) alternating with times when your symptoms are more active (relapses or ‘flare-ups’).  

Here’s a guide to the common symptoms of Inflammatory Bowel Disease (IBD).

If you’d like to know more, please contact our Information Service or browse our free booklets, guides and information sheets


Steve Redgrave

With the right medical treatment, I've been able to keep the illness under control and continue with my life, both in training during my career as a professional athlete and in my life beyond the boat.

Sir Steve Redgrave, multiple Olympic gold medallist
Diagnosed with Ulcerative Colitis in 1991.

The main symptoms of IBD:

  • Diarrhoea. This is sometimes mixed with blood, mucus and pus.
  • Cramping pains in the abdomen. These can be very severe and often occur before passing a stool.
  • Tiredness and fatigue. This can be due to the illness itself, from anaemia (see below) from the side effects of some of the drugs used for IBD or from a lack of sleep if you have to keep getting up at night with pain or diarrhoea.
  • Feeling generally unwell. Some people may feel feverish.
  • Loss of appetite and loss of weight. Weight loss can be due to the body not absorbing nutrients from the food you eat because of the inflammation in the gut.
  • Anaemia (a reduced number of red blood cells). You are more likely to develop anaemia if you are losing a lot of blood and are not eating much.
  • Mouth ulcers.

Some people with IBD, particularly Crohn’s, may develop complications, including:

  • Strictures.  This is when there is ongoing inflammation and then healing in the bowel which may cause scar tissue to form.  This can create a narrow section of the bowel, called a stricture.
  • Fistulas. A fistula is an abnormal channel or passageway connecting one internal organ to another, or to the outside surface of the body.  These are more common in people with Crohn’s Disease.

IBD can sometimes affect other parts of the body, including:

  • Joints. Inflammation of the joints, often known as arthritis, means that fluid collects in the joint space causing painful swelling.  It usually affects the large joints of the arms and legs, including the elbows, wrists, knees and ankles.  
  • Eye inflammation. The most common eye condition affecting people with IBD is episcleritis, which affects the layer of tissue covering the sclera, the white outer coating of the eye, making it red, sore and inflamed.

Further information...

Crohn's Disease and Ulcerative Colitis can have some very awkward and distressing symptoms. But there are ways to manage some of these and make life that little bit easier.

We’ve collected useful facts, suggestions and tips from health professionals and people who have experienced these symptoms. We’ve put them together in a series of information sheets that are free to download:

You may also be concerned about links between IBD and other conditions. See information on:

Ulcerative Colitis, Edition 9 - last review June 2017. Next planned review 2020.

Crohn's Disease, Edition 7a - last review October 2017. Amended July 2017. Next planned review 2019.


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