The large intestine (also called the colon) consists of the ascending, transverse, descending and sigmoid colon. The rectum is the last portion of the large intestine.

What is ulcerative colitis?

Ulcerative colitis (UC) causes irritation and ulcers (open sores) in the large intestine (also called the colon). It belongs to a group of conditions called inflammatory bowel disease (IBD). It often causes diarrhea with blood, cramping and urgency. Sometimes these symptoms can wake a person up at night to go to the bathroom as well.

The inflammation in ulcerative colitis usually starts in the rectum, which is close to the anus (where poop leaves your body). The inflammation can spread and affect a portion of, or the entire colon. When the inflammation occurs in the rectum and lower part of the colon it is called ulcerative proctitis. If the entire colon is affected it is called pancolitis. If only the left side of the colon is affected it is called limited or distal colitis.

The severity of UC depends on the amount of inflammation and the location. Everyone is a little different. You could have severe inflammation in the rectum (small area) or very mild inflammation in the entire colon (large area).

If you have ulcerative colitis, you may notice a pattern of flare-ups (active disease), when symptoms are worse. During times of remission, you might have little to no symptoms. The goal with therapy is to remain in remission as long as possible (years).

About half of the people diagnosed with ulcerative colitis have mild symptoms. Others suffer frequent fevers, bloody diarrhea, nausea and severe abdominal cramps. Ulcerative colitis may also cause problems such as arthritis, inflammation of the eye, liver disease and osteoporosis. It is not known why these problems occur outside the colon. Scientists think these complications may be the result of inflammation triggered by the immune system. Some of these problems go away when the colitis is treated.

Ulcerative colitis can occur in people of any age, but it usually starts between the ages of 15 and 30, and less frequently between 50 and 70 years of age. It affects men and women equally and appears to run in families, with reports of up to 20% of people with ulcerative colitis having a family member or relative with ulcerative colitis or Crohn’s disease. In addition, about 20% of patients are diagnosed before they are 20 years old and it can occur in children as young as two years of age.

What’s the difference between colitis and ulcerative colitis?

Colitis means your colon is inflamed, or irritated. This can be caused by many things, such as infections from viruses or bacteria. Ulcerative colitis is more severe because it is not caused by an infection and is lifelong.

How common is ulcerative colitis?

Ulcerative colitis isn’t an uncommon condition. Together with Crohn’s disease, another type of inflammatory bowel disease, it affects up to 1 in 250 people in North America and Europe.

Who gets ulcerative colitis?

Anyone at any age, including young children, can get ulcerative colitis. Your chance of getting it is slightly higher if you:

  • Have a close relative with inflammatory bowel disease (IBD).
  • Are between 15 and 30 years old, or older than 60.
  • Are Jewish.
  • Eat a high-fat diet.
  • Use frequent nonsteroidal anti-inflammatory drugs (NSAIDS) like ibuprofen (Advil® or Motrin®).

What causes ulcerative colitis?

Researchers think the cause of ulcerative colitis is complex and involves many factors. They think it’s probably the result of an overactive immune response. The immune system’s job is to protect the body from germs and other dangerous substances. But, sometimes your immune system mistakenly attacks your body, which causes inflammation and tissue damage.

What are the symptoms of ulcerative colitis?

Ulcerative colitis symptoms often get worse over time. In the beginning, you may notice:

  • Diarrhea or urgent bowel movements.
  • Abdominal (belly) cramping.
  • Tiredness.
  • Nausea.
  • Weight loss.
  • Anemia (reduced number of red blood cells).

Later you may also have:

  • Blood, mucous, or pus in bowel movements.
  • Severe cramping.
  • Fever.
  • Skin rashes.
  • Mouth sores.
  • Joint pain.
  • Red, painful eyes.
  • Liver disease.
  • Loss of fluids and nutrients.

Symptoms are similar in pediatric ulcerative colitis and may also include delayed or poor growth. Some ulcerative colitis symptoms in children can mimic other conditions, so it is important to report all symptoms to your pediatrician.

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