Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. The therapy may also damage healthy cells in the lining of the intestines.
People who have radiation therapy to the belly or pelvic area are at risk. These may include people with cervical, pancreatic, prostate, uterine, or colon and rectal cancer.
Symptoms may vary, depending on which part of the intestines received the radiation. Symptoms can also be different if you have chemotherapy at the same time as the radiation.
Symptoms may occur during or shortly after radiation treatment (called acute radiation enteritis), or long after the treatment.
Changes in bowel movements may include:
- Bleeding or mucus from the rectum
- Diarrhea or watery stools
- Feeling the need to have a bowel movement most or all of the time
- Pain in the rectal area, especially during bowel movements
Other symptoms can include:
- Loss of appetite
- Nausea and vomiting
Most of the time, these symptoms get better within 2 - 3 months after radiation treatment ends.
When symptoms become long-term (chronic), other problems may include:
- Abdominal pain
- Bloody diarrhea
- Greasy or fatty stools
- Weight loss
Starting a low-fiber diet on the first day of radiation treatment may help you avoid problems. The best choice of foods depends on your symptoms.
Some things can make symptoms worse, and should be avoided. These include:
- Alcohol and tobacco
- Almost all milk products
- Coffee, tea, chocolate, and sodas with caffeine
- Foods containing whole bran
- Fresh and dried fruits
- Fried, greasy, or fatty foods
- Nuts and seeds
- Popcorn, potato chips, and pretzels
- Raw vegetables
- Rich pastries and baked goods
- Some fruit juices
- Strong spices
Foods and drinks that are better choices include:
- Apple or grape juice
- Applesauce, peeled apples, and bananas
- Eggs, buttermilk, and yogurt
- Fish, poultry, and meat that has been broiled or roasted
- Mild, cooked vegetables, such as asparagus tips, green or black beans, carrots, spinach, and squash
- Potatoes that have been baked, boiled, or mashed
- Processed cheeses, such as American cheese
- Smooth peanut butter
- White bread, macaroni, or noodles
Your doctor may have you use certain medicines such as:
- Drugs that help decrease diarrhea, such as loperamide
- Pain medicines
- Steroid foam that coats the lining of the rectum
- Special enzymes to replace enzymes from the pancreas
Other things you can do include:
- Eating foods at room temperature
- Eating small meals more often
- Drink plenty of fluids (up to 12 8-ounce glasses) every day when you have diarrhea. Some people will need fluids given through a vein (intravenous fluids).
Your health care provider may choose to decrease your radiation for a short period of time.
There often are no good treatments for chronic radiation enteritis. However, medicines such as cholestyramine, diphenoxylate-atropine, loperamide, or sucralfate may help. You may need to consider surgery to either remove or go around (bypass) a section of damaged intestine.
When the abdomen receives radiation, there is always some nausea, vomiting, and diarrhea. In most cases, the symptoms get better within 2 - 3 months after treatment ends.
However, when this condition develops, symptoms may last for a long period of time. Long-term (chronic) enteritis is rarely curable.
When to Contact a Medical Professional
Call your health care provider if you are having radiation therapy or have had it in the past and are having a lot of diarrhea or stomach pain and cramping.
Radiation enteropathy; Radiation-induced small bowel injury; Post-radiation enteritis
Czito BG, Willett CG. Radiation injury. In: Feldman M, Friedman LS, Brandt LJ, eds.Sleisenger & Fordtran's Gastrointestinal and Liver Disease
National Cancer Institute.Gastrointestinal Complications PDQ
Prather C. Inflammatory and anatomic diseases of the intestine, peritoneum, mesentery, and omentum. In: Goldman L, Schafer AI, eds.Goldman's Cecil Medicine
Update Date 8/11/2014
Updated by: Jenifer K. Lehrer, MD, Department of Gastroenterology, Frankford-Torresdale Hospital, Aria Health System, Philadelphia, PA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.