This is a chronic inflammatory disease which causes stomach pains, diarrhoea, and weight loss. The disease is characterised by periods of activity and remissions. It typically affects the lower part of the small intestine (ileum) or the large intestine (colon), but it can affect any part of the digestive system. The affected areas become red and swollen and ulceration may occur. As the ulcers heal, the formation of scar tissue makes the intestine increasingly narrow, leading to obstruction. There is no cure for Crohn's disease, but the symptoms can be treated and the periods of remission can be made to last several years.

The symptoms vary and depend on the severity and location of the disease.
Many patients only have mild symptoms for a long time and have often had the disease for several years before it is diagnosed.
Periods of mild fever, sometimes with blood in the stools, and pain in the lower right part of the abdomen.
Loss of appetite.
Unintentional weight loss.
Boils (cavities containing pus) and fistulas (formation of small passages that connect the intestine with other organs or the skin).
General malaise.