What is ulcerative colitis (UC)?
Ulcerative colitis (UC) is an ongoing health problem that causes inflammation and bleeding sores called ulcers in the top layers of the large intestine (colon) and rectum. It most often occurs in the lower part of the colon and rectum, but may affect the whole colon. When UC only occurs in the rectum, it is called proctitis. Most people find out they have UC between the ages of 15 and 40 years.
