Radiation enteritis is swelling (inflammation) of the lining of the small intestine due to radiation therapy, a type of cancer treatment.

Anyone with cancer needing radiation therapy to the belly area is at risk. This may include people with cervical, uterine, or rectal cancer.

If the damage lasts only a short time, it is called acute radiation enteritis. If damage causes lasting inflammation in the intestine, it is called chronic radiation enteritis.

• Anorexia
• Diarrhea
• Nausea
• Vomiting
• Weight loss

The health care provider will do a physical exam and ask you questions about your medical history.

Tests may include:

• Colonoscopy
• Upper endoscopy

A sample (biopsy) of suspicious tissue may be taken during these procedures.

Ways to control the symptoms of radiation enteritis include:

• Avoid fats and dairy foods (see: lactose intolerance)
• Eat small meals more often
• Take medications that help decrease diarrhea, such as loperamide (talk to your doctor)

Sometimes patients need fluids given through a vein (intravenous fluids). A medication called octreotide may help for more severe symptoms.

It may be possible to stop or reduce the dosage of radiation for a short period of time. It is important for you to report all symptoms to your doctor so adjustments can be made as soon as possible to prevent permanent damage.

Unfortunately, there often are no good treatments for chronic radiation enteritis.

When the abdomen is radiated, there is always some nausea, vomiting, and diarrhea. In most cases, the symptoms get better when the treatments are completed.

However, when this condition develops, symptoms may last for a long period of time. Long-term (chronic) enteritis is rarely curable.

• Bleeding and anemia
• Dehydration
• Malabsorption
• Malnutrition
• Weight loss

Call your health care provider if you are undergoing radiation therapy or have had radiation in the past and are experiencing a lot of diarrhea.

By limiting the amount of radiation given to the intestines (if possible), you can avoid radiation enteritis.

Cho LC, Antoine JE. Radiation Injury to the Gastrointestinal Tract. In: Feldman M, Friedman LS, Sleisenger MH, eds. Sleisenger & Fordtran's Gastrointestinal and Liver Disease. 8th ed. Philadelphia, Pa: Saunders Elsevier; 2006: chap 38.