Confused about Ischemic Colitis and Colitis?

Quincy AdamUC Learn


There are several different types of colitis, but the one you may be most familiar with, ulcerative colitis, is quite different from ischemic colitis.1

Ulcerative Colitis is the chronic irritation and swelling (inflammation) of the large intestine with small sores called ulcers, and usually affects younger people.2

Ischemic colitis occurs most often in people aged 60 and older and the inflammation and injury in the colon is caused by not enough blood flow to the large intestine.2 For many people, it is mild to moderate and not a medical emergency, and can be treated with antibiotics and resting the large intestine (no food or drink).  However, when severe, it may come on suddenly and result in serious problems if left untreated.2

Call 911 or head to the emergency room, if you have pain in the lower abdomen and you have had diarrhea that is bloody2.

Learn more about the symptoms of ischemic colitis:

The intestines perform a variety of essential tasks in your body – from absorbing nutrients from food to passing wastes from the body. These activities require oxygen and other vital substances that are supplied by your blood flow.  The blood supply to the large intestine keeps it performing its important tasks and keeps the tissue alive.3 If there is a blockage, the blood supply is reduced and without oxygen from the blood, the tissues in your colon can become damaged or die quickly.3

This may lead to some very serious complications that may require surgery: 4

  • gangrene (tissue death)
  • bowel inflammation
  • bowel blockage
  • perforation (hole) in your intestine
  • bleeding

Causes of Reduced Blood Flow

There are a number of factors that can lead to reduced blood flow to the colon and put you at greater risk for ischemic colitis:5

  • A buildup of fatty deposits called plaque on the walls of the arteries can cause hardening in the arteries that carry blood to the abdomen, reducing blood flow to the colon.5 People who have coronary artery disease or peripheral vascular disease are at higher risk because of plaque buildup.6
  • Very low blood pressure is associated with major surgery, heart failure, trauma and shock and puts you at much greater risk for a reduced blood flow to the colon.
  • Any kind of blockage in the bowel can increase risk. This may happen when you have had a hernia, a tumor or scar tissue has formed after a surgery in the abdomen.
  • If you have had a surgical procedure involving the heart or blood vessels, the digestive system or gynecological procedure, you may be at higher risk. Surgery on the large artery (aorta) – that pumps blood from your heart to the rest of your body is an example, as well as surgery to repair an aortic aneurysm (a bulge in an artery) is another.
  • Medical disorders that affect your blood, such as inflammation of the blood vessels, lupus and sickle cell anemia increase risk.
  • A blood clot in the artery that supplies blood to the colon can cause ischemic colitis, more common for people who have an irregular heartbeat.
  • Certain medications can increase your risk, including some heart and migraine medications, estrogen, antibiotics, the decongestant pseudophedrine, some medications for irritable bowel syndrome, and cocaine or methamphetamine.

Read more about what experts say can cause reduced blood flow:

7 Risk Factors for Ischemic Colitis5,6

  1. Age: more common in people older than age 60. In younger people, blood clotting problems or problems with the blood vessels may increase risk.
  2. Clotting abnormalities: some inherited problems affecting the way the blood clots and can increase risk.
  3. High Cholesterol: leads to hardening of the arteries.
  4. Reduced Blood Flow: Low blood pressure, heart failure and shock put you at higher risk.
  5. Aortic Surgery: if you have had a procedure on the large artery (aorta) that pumps blood from your heart to the rest of your body, you may be at higher risk. An example is a procedure to repair an aortic aneurysm – a bulge in an artery.
  6. Heavy exercise: marathon runners are at higher risk because of reduced blood flow to the colon. Dehydration can also put you at higher risk.
  7. Medications that can cause constipation or trigger an attack: the decongestant pseudoephedrine, certain antibiotics and migraine medications, and illegal substances such as cocaine and methamphetamines all increase risk.

For more information on the risk factors for ischemic colitis:

How is ischemic colitis diagnosed and treated?

Your doctor would run several diagnostic tests, and if you have a very mild case, you may just be closely monitored and take antibiotics and a liquid diet at home.  If chronic and mild to moderate, you doctor may require you to be hospitalized and treated with antibiotics and IV fluids, to give the bowel a rest from food and drink.7

  • Imaging such as an ultrasound or CT scan in order to see your blood vessels and intestines.
  • Angiogram is another imaging test that allows your doctor to see inside your arteries and where there is blockage.
  • Stool sample or colonoscopy.
  • Blood tests can also check your white blood cell count – when it is high it can mean you have a medical emergency that may require medications or surgery to remove a blockage or any dead tissue.
  • Surgery is only necessary when the ischemic colitis is acute and severe and there is damage to the colon.

Reduce Your Risk with a Healthy Lifestyle

By reducing your risk of plaque buildup and hardening of your arteries, you can also reduce your risk of ischemic colitis. You know the basics! 8

  • Exercise regularly
  • Eat a healthy diet and stay hydrated
  • Keep tabs on your blood cholesterol and blood pressure
  • Don’t smoke
  • Treat heart conditions that can lead to blood clots such as irregular heartbeat
  • Don’t use illegal substances such as cocaine or methamphetamine
  • Talk to your doctor about any prescription or other medications you are taking

Look for tips here on reducing your risk: and here:

  1. Facts about Colitis. [accessed on April 26, 2017]
  2. What Makes Colitis Ischemic or Ulcerative? [accessed on April 26, 2017]
  3. American College of Gastroenterology. Patient Education and Resource Center. What is Intestinal Ischemia? [accessed on April 25, 2017]
  4. The Mayo Clinic. Complications of Ischemic Colitis. [accessed on April 26, 2017]
  5. The Mayo Clinic. Risk Factors for Ischemic Colitis. [accessed on April 26, 2017]
  6. FitzGerald JF, Hernandez LO. “Ischemic Colitis”. Clin Colon Rectal Surg. 2015 Jun; 28(2):93-98. [accessed on April 26, 2017]
  7. The Mayo Clinic. Ischemic Colitis Treatment. [accessed on April 26, 2017]
  8. Ischemic Colitis. [accessed on April 26, 2017]