Inflammatory bowel disease, or IBD, is the common name used to describe a set of two chronic diseases of the intestinal tract: Crohn’s disease and ulcerative colitis. These diseases inflame the lining of the gastrointestinal (GI) tract and disrupt the body's ability to digest food, absorb nutrition, and eliminate waste in a healthy manner. They are lifelong diseases and people can experience acute periods of active disease or flares and periods of remission.

Ulcerative colitis is more localized in nature than Crohn’s disease. Typically, the disease affects the colon (large intestine) including the rectum and anus and inflames the inner lining of bowel tissue. It often starts at the rectum, extending upwards in a continuous manner through the colon.