Ulcerative colitis

What is ulcerative colitis?

Ulcerative colitis (UC) represents a form of GI tract inflammation. Inflammation from ulcerative colitis typically begins by affecting the rectum and then may spread further into the colon. Typically, only the innermost colon lining is affected and ulcers may appear on the surface. The affected area is normally continuous and not patchy.

Inflammatory bowel disease and ulcerative colitis

UC is a form of inflammatory bowel disease (IBD). IBD is defined by chronic inflammation of the gastrointestinal (GI) tract and can be progressive. IBD is also associated with eye inflammation, skin issues, and joint pain or swelling. IBD can be confused with irritable bowel syndrome (IBS), a separate condition that is unrelated to GI inflammation.

What causes ulcerative colitis?

UC is thought to be caused by an overreaction from your immune system. The specific cause of UC is unknown but the state of your immune system, environmental factors, and your genetics can all impact the condition. You’re more likely to develop it if a parent or sibling has it. UC is more common in those of Jewish-European decent and typically begins between the ages of 15 and 30.


The most common symptom of UC is frequent, loose, bloody stools.

Other symptoms include

  • Abdominal pain and discomfort
  • Blood or pus in stool
  • Frequent diarrhea
  • Fatigue
  • Decreased appetite and weight loss
  • Tenesmus

Tenesmus is a constant and sudden feeling that you have to pass stool.

Symptoms of severe UC may include more than six loose stools per day, fever, and anemia.


If you are experiencing symptoms of UC, your doctor can perform a number of exams to look for inflammation in your GI tract. These include:

A small flexible tube with a camera can be inserted into many areas of your GI tract. A biopsy can also be done during this exam—where a cell sample is taken for testing.
Imaging tests
A CT or MRI can show abnormalities in the GI tract.


A wide range of treatment options can control symptoms of UC. With treatment, many UC patients successfully maintain remission or remain symptomless over a period of time. A flare-up is when symptoms appear again or suddenly worsen.

Medications that treat and control inflammation are the most common treatment method. The medication your doctor may prescribe will depend on how severe your UC is.

illustrations showing steps in removing colon

Surgery is an option to treat UC and it may be recommended if your large intestine becomes significantly damaged or you have severe, chronic, and debilitating symptoms. A proctocolectomy is a multi-step procedure used to treat the disease. It involves removing the colon and rectum (point A above), creating a temporary ileostomy and J pouch (point B above) and using the ileal reservoir as a rectum (point C above).

If you are experiencing symptoms of ulcerative colitis, see a health care provider.

Last reviewed: 
July 2018

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