Ischemic colitis

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at August 3, 2016
StartDiseasesIschemic colitis

Ischemic colitis is a condition affecting the large intestine (also known as the colon), which typically occurs in adults over the age of 60. In most cases, people are cured of the problem in a few days, but severe cases may require surgery.


Definition & Facts

Ischemic colitis occurs when blood flow to the large intestine is blocked or diminished, and it can happen for a variety of reasons. The decrease in blood flow reduces the amount of oxygen carried to the cells of the digestive system and can cause damage to the colon.

Because the symptoms of ischemic colitis overlap with many other gastrointestinal diseases, it can be difficult to diagnose. While most people recover from a mild case of ischemic colitis, there are severe cases that may require surgery to repair a damaged colon.

The main symptom of the condition is pain, typically on the left side of the abdomen, accompanied by diarrhea and nausea. Pain occurring on the right side of the body can also occur and usually indicates a more severe underlying problem.

Symptoms & Complaints

The most common complaint from people suffering from ischemic colitis is pain occurring in the abdomen. It is more common for people to feel pain on the left side of the body. The pain can come on suddenly or can worsen gradually. Other symptoms include diarrhea or nausea.

Another common symptom is blood in stool. In some cases, a person might pass only blood without stool.

If the patient experiences pain on the right side of the abdomen, the case of ischemic colitis may be more severe. The same blood vessels that flow into the right side of the colon also feed directly into the small intestine. Pain on the right side can indicate a blockage with the small intestine as well.

If the blood flow to the small intestine is blocked, the tissue of the intestines can die quite quickly. This results in a life-threatening situation that requires immediate surgery to clear the obstructions and remove any dead tissue.

It is recommended that a person seek medical attention if he or she is not able to comfortably sit in any one position because his or her abdominal pain is so severe. One should always see a doctor if any of the symptoms drastically worsen. Very serious complications with ischemic colitis can be prevented with early diagnosis and treatment.


Because ischemic colitis is simply decreased blood flow to the large intestines, it can be difficult to find one definite cause consistent with every case of the condition. There are, however, several factors that can increase a person’s likelihood to become afflicted with ischemic colitis. Having a build-up of fatty deposits on the walls of the arteries (atherosclerosis) can increase the chances of having blood flow blocked.

Certain diseases that affect a person’s blood, such as sickle-cell disease or lupus, can make a person more likely to have ischemic colitis. Low blood sugar levels that can be a result of cardiovascular disease, trauma, shock, or major surgery, especially if the surgery was cardiac surgery, can also affect a person’s likelihood to experience this condition.

Although rare, some medications such as hormone medications, antibiotics, chemotherapy, and medications to treat heart disease and migraines can cause ischemic colitis.

Age is considered a risk factor. Most patients are over the age of 60. If a young adult is diagnosed with ischemic colitis it can indicate a blood clotting disorder or inflamed blood vessels (vasculitis). 

Diagnosis & Tests

The symptoms of ischemic colitis overlap with other gastrointestinal disorders, so a doctor may perform several tests to help rule out other diseases. An ultrasound may be ordered to take images of the colon. This can help rule out inflammatory bowel disorder, or IBD. Stool samples can help determine if an infection is present.

A magnetic resonance angiography (MRA) can look for blocked arteries by taking a close look at the blood flow through a person’s veins. This test may be performed if the doctor believes that the small intestine may be affected also.

A doctor may also order a blood test. A high white blood cell count can indicate an acute case of ischemic colitis. Finally, a colonoscopy can take images specifically of the colon to check for cancer. Colonoscopies can also be taken during follow-up doctor's visits to ensure that treatment was successful. 

Treatment & Therapy

Treatment of ischemic colitis varies depending on the severity of the condition and any underlying diseases. Most people experience only one episode of the condition and will have made a recovery within several days. In such cases, there is minimal intervention from a doctor required, although antibiotics may be prescribed to prevent infection.

In cases of dehydration, IV fluids might be administered to help re-hydrate the patient. A doctor may prescribe medication to dissolve blood clots if these are found to be the cause of the blockage. Medication that helps widen the blood vessels can help restore blood flow to the colon and may be prescribed.

In extreme cases of the condition, surgery may be necessary. The surgery can help repair a damaged colon by patching a hole or rupture, bypassing any blockages, or removing dead, scarred, or narrowed portions of the colon that are found to be the cause of the decreased blood flow. In patients with heart disease or low blood pressure, surgery may be recommended to cure ischemic colitis. 

Prevention & Prophylaxis

Ischemic colitis is difficult to prevent because there is not one definite cause of the condition. Most people only experience a single episode with the condition and will recover in a matter of days. If doctors find that the condition was caused by a medication, it may be recommended to discontinue use of the medication.

An episode of ischemic colitis may be cause for further testing to help diagnose any underlying diseases, such as blood clotting abnormalities, which may have caused the ischemic colitis.

Maintaining a healthy lifestyle can help reduce the risk of underlying cardiovascular diseases that can cause ischemic colitis. It is recommended to quit smoking and maintain a healthy diet to prevent this and other conditions involving the cardiovascular system.