Ulcerative colitis is one of the Inflammatory Bowel Diseases (IBD). Ulcerative colitis affects only the colon. It is a chronic (long term) disease that recurs over a lifetime, which is marked by periods of remission (few symptoms) and exacerbation (heavy symptoms). The inflammation involves the entire rectum and extends up the colon in a solid wave. Ulcerative colitis does not skip from one area to the next. With ulcerative colitis the lesions affect only the innermost lining of the colon.