Ischemic Colitis

Front view of colon showing arteries supplying blood to colon.

Ischemic colitis happens when blood flow to the colon is reduced or blocked. You may have bloody diarrhea and severe belly pain. Other symptoms are vomiting, fever, and fainting. Diarrhea can lead to severe dehydration. This is the rapid loss of the fluids your body needs to work. Because of the severe pain and the risk for dehydration, this health problem should be treated right away.

Causes of ischemic colitis

Experts aren't sure what causes ischemic colitis. In some cases, a sudden drop in blood pressure may lead to it. So, too, can dehydration. The condition is more likely in people with blood clotting problems or heart and blood vessel disease.

Diagnosing ischemic colitis

Your healthcare provider will ask about your symptoms. Having severe belly pain and bloody diarrhea is often enough to diagnose ischemic colitis. After these symptoms are treated, you may need:

  • A colonoscopy. This test helps rule out other colon problems. It uses a thin, flexible scope with a light and camera on the end. Your healthcare provider puts the scope into the rectum to the colon. The scope sends pictures from inside the colon to a video screen. A small sample of tissue (biopsy) from the colon may be taken for testing in a lab.

  • Other tests such as a CT scan. These are done to check the belly.

Treating ischemic colitis

Episodes are treated in the hospital. You may stay in the hospital for several days or longer:

  • An IV line is put into a vein in your hand or arm. You will be given fluids through the IV to treat dehydration. You are also given IV pain medicines if you need them.

  • You may be given IV antibiotics. These medicines treat infection.

  • To rest the bowel, you will not eat or drink for a few days. In rare cases, when symptoms are very severe, you will be given nutrition through the IV.

  • If you lost a lot of blood during the episode, you may get a blood transfusion.

  • In rare cases, an episode causes severe damage to the colon. In this case, surgery may be needed to take out the damaged part. Your healthcare provider can tell you more.


While you are being treated, your healthcare provider will work to find the cause of your ischemic colitis. After you get better, you may need to make lifestyle changes, such as quitting smoking. You may also have to take medicines to lower your risk of another episode. Call 911 if your symptoms come back.