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Ulcerative Colitis

Condition Basics

What is ulcerative colitis?

Ulcerative colitis is a disease that causes inflammation and sores (ulcers) in the lining of the large intestine, or colon. It usually affects the lower section and the rectum. But it can affect the entire colon. In general, the more of the colon that's affected, the worse the symptoms will be.

What causes it?

Experts aren't sure what causes ulcerative colitis. It might be caused by the immune system overreacting to normal bacteria in the digestive tract. Or other kinds of bacteria and viruses may cause it. You are more likely to get it if other people in your family have it.

What are the symptoms?

The main symptoms of ulcerative colitis are belly pain or cramps, diarrhea, and bleeding from the rectum. In severe cases, people may have diarrhea 10 to 20 times a day. Some people also may have a fever, not feel hungry, and lose weight. In most people, the symptoms come and go.

How is it diagnosed?

To diagnose ulcerative colitis, a doctor will ask about your symptoms, do a physical exam, and do a number of tests. These tests may include colonoscopy, blood tests, and stool sample testing. Testing can help rule out other problems that can cause similar symptoms, such as Crohn's disease and irritable bowel syndrome.

How is ulcerative colitis treated?

Medicines can help reduce your symptoms and help you avoid new flare-ups. Changes in your diet might also help with some symptoms. If you have severe symptoms and medicines don't help, you may need surgery to remove your colon. This cures ulcerative colitis.

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The main symptoms of ulcerative colitis are:

  • Belly pain or cramps.
  • Diarrhea.
  • Bleeding from the rectum.

Some people also may have a fever, may not feel hungry, and may lose weight. In severe cases, people may have diarrhea 10 to 20 times a day.

The disease can also cause other problems, such as joint pain, eye problems, or liver disease.

In most people, the symptoms come and go. Some people go for months or years without symptoms (remission) and then have a flare-up. A few people have symptoms all the time.

What Happens

Ulcerative colitis may be mild, moderate, or severe.

Most people have periods of remission (when the condition is not active) that may last up to several years. These periods are interrupted by occasional flare-ups of moderate symptoms. Some people who have ulcerative colitis have symptoms all the time.footnote 1

Children may have the same symptoms that adults have. Also, children with the disease may grow more slowly than normal and go through puberty later than expected.

Complications of ulcerative colitis

Problems from ulcerative colitis can include:

  • Narrowed areas of the intestine (strictures). They can make it hard to pass stools.
  • Increased risk of cancer of the colon and rectum. This risk is higher than average if you have had ulcerative colitis for 8 years or longer.
  • Complications outside the digestive tract. These include joint pain, skin problems, and eye problems.
  • The colon swelling to many times its normal size. This is called toxic megacolon. It's rare, but it needs treatment right away.
  • Other rare complications, such as scarring of the bile ducts and the pancreas.
  • Inflammatory bowel disease, which also increases the risk of melanoma, a serious type of skin cancer. Your doctor may recommend regular screening by a dermatologist.footnote 2

Irritable bowel syndrome

Some people who have ulcerative colitis also have irritable bowel syndrome (IBS). It isn't as serious as ulcerative colitis. IBS causes belly pain along with diarrhea or constipation.

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When to Call

Ulcerative Colitis: When to Call

Call a doctor now if you have been diagnosed with ulcerative colitis and you have:

  • Fever over 38.3°C (101°F) or shaking chills.
  • Light-headedness, passing out, or a rapid heart rate.
  • Stools that are almost always bloody.
  • Severe dehydration, such as passing little or no urine for 12 or more hours.
  • Severe belly pain with or without bloating.
  • Pus draining from the area around the anus or pain and swelling in the anal area.
  • Repeated vomiting.
  • Not passing any stools or gas.

If you have any of these symptoms and you have been diagnosed with ulcerative colitis, your disease may have become significantly worse. Some of these symptoms also may be signs of toxic megacolon. This is a condition in which the colon swells to many times its normal size. It requires emergency treatment. Left untreated, it can cause the colon to leak or rupture. This can be fatal.

People with ulcerative colitis usually know their normal pattern of symptoms. Call your doctor if there is a change in your usual symptoms or if:

  • Your symptoms become significantly worse than usual.
  • You have persistent diarrhea for more than 2 weeks.
  • You have lost weight.

Watchful waiting

Watchful waiting is not a good choice when you have any of the above symptoms. If your symptoms are caused by ulcerative colitis, delaying the diagnosis and treatment may make the disease worse. And it can increase your risk of other problems.

Even when the disease is in remission, your doctor will want to see you regularly to check for complications. Some of these problems can be hard to detect. It's always a good idea to call your doctor's office for advice.

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Examinations and Tests

To diagnose ulcerative colitis, a doctor will ask about your symptoms, do a physical exam, and do a number of tests. Testing can help rule out other problems that can cause similar symptoms, such as Crohn's disease and irritable bowel syndrome.

Tests that may be done include:

  • Colonoscopy. In this test, a doctor uses a thin, lighted tool to look at the inside of your entire colon. At the same time, the doctor may take a sample (biopsy) of the lining of the colon.
  • Blood tests to check for infection or inflammation.
  • Stool sample testing to look for blood, infection, and white blood cells.

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Treatment Overview

Treatment for ulcerative colitis depends mainly on how bad the disease is. Your doctor will help you find treatments that reduce your symptoms and help you avoid flare-ups. Options include:

  • If your symptoms are mild, you may only need to use over-the-counter medicines for diarrhea (such as Imodium). Talk to your doctor before you take these medicines.
  • Many people need prescription medicines, such as steroid medicines or other medicines that reduce the body's immune response. These medicines can stop or reduce symptoms and prevent flare-ups.
Changes in your diet.

If certain foods make your symptoms worse, it makes sense to not eat those foods. But be sure to eat a healthy, varied diet to keep your weight up and to stay strong.


If you have severe symptoms and medicines don't help, you may need surgery to remove your colon. This cures ulcerative colitis. It also prevents colon cancer.

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You can take steps at home to reduce symptoms of ulcerative colitis and take care of yourself.

  • Take over-the-counter medicines.

    If you have only mild symptoms, antidiarrheal medicines may help. For disease in the rectum alone, you can try medicines given in a suppository, enema, or foam.

  • Avoid medicines that can make ulcerative colitis worse.

    In general, doctors recommend that you don't use non-steroidal anti-inflammatory drugs (NSAIDs, such as ibuprofen or naproxen). These medicines may cause flare-ups. But some people may be more likely to have flare-ups from NSAIDs than other people. Talk to your doctor about whether to avoid these medicines.

  • Change your diet.

    A change in your diet may help reduce symptoms. Keep a food diary to find out which foods make your symptoms worse. During a flare-up, avoid or reduce these foods.

    Instead of cutting out a whole group of high-nutrient foods, try replacing them with healthy choices.

  • Get support.

    Ulcerative colitis can affect every aspect of your life. You may want to seek counselling or social support from family, friends, or clergy. Or look for a support group.

  • Learn about ostomy care.

    If you have had or are planning to have surgery that will create an ostomy, you may feel self-conscious or embarrassed. After a period of adjustment, most people are able to resume all of their usual activities. In fact, you may feel better than before surgery because you may no longer have painful symptoms. Support groups are available for people with ostomies.

Children tend to have a harder time than adults in managing the disease. So the support of a parent is very important.

Children may feel self-conscious if they don't grow as fast as other children their age. Encourage your child to take medicine as prescribed. Offer your help with the treatment so that your child can feel better, start growing again, and lead a more normal life.

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Medicines are the main treatment for ulcerative colitis. They control or prevent inflammation in the intestines. They also help relieve symptoms. And they may help heal damaged tissues and prevent the need for surgery.

Antidiarrheal medicines and enemas or suppositories may help relieve symptoms. Your doctor may also prescribe aminosalicylates or steroid medicines. In more severe cases, medicines that suppress the immune system, biologics, or intravenous (I.V.) corticosteroids may be used.

The choice of medicines usually depends on how bad the disease is and which part of the colon is affected. It can also depend on any complications you may have.

If you are pregnant or are planning to become pregnant, talk to your doctor about which medicines might be okay for you to use.


Surgery that removes the large intestine (colon) can cure ulcerative colitis. It can also often cure problems that the disease causes outside of the colon, such as skin and eye problems. But it may not cure liver problems or joint problems.

People need surgery for different reasons. For example, it may be needed when treatment isn't working or when holes form in the large intestine.

There are two types of surgery.

Ileoanal anastomosis.

The surgeon removes some or all of the large intestine, and the lining of the rectum. Then he or she connects the small intestine to the anal canal. After this surgery, you can have bowel movements without an ostomy.

Proctocolectomy and ileostomy.

The surgeon removes the large intestine and rectum. Then he or she sews the anus closed and creates an opening to the outside of the body. After this surgery, you'll need an ostomy.

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  1. Osterman MT, Lichtenstein GR (2010). Ulcerative colitis. In M Feldman et al., eds., Sleisenger and Fordtran's Gastrointestinal and Liver Disease, 9th ed., vol. 2, pp. 1975–2013. Philadelphia: Saunders Elsevier.
  2. Singh S, et al. (2014). Inflammatory bowel disease is associated with an increased risk of melanoma: A systematic review and meta-analysis. Clinical Gastroenterology Hepatology, 12(2): 210–218. DOI: 10.1016/j.cgh.2013.04.033. Accessed March 25, 2015.


Current as of: March 21, 2023

Author: Healthwise Staff
Clinical Review Board
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