There is no known cause of IBS. It is believed to be the result of an infection of the intestines.
The objective of treatment is to relieve symptoms. Lifestyle changes can be helpful in some cases of IBS. For example, regular exercise and improved sleep habits may reduce anxiety and help relieve bowel symptoms.
Your doctor may prescribe anticholinergic medicines to control intestinal muscle spasms. Dietary changes can be helpful such as avoiding large meals, avoiding foods and drinks that stimulate the intestines, and increasing fiber in diet.