Constipation and Diarrhea

Cancer and related treatments can cause digestive problems such as constipation or diarrhea.


Decreased activity and poor nutrition can cause constipation. To relieve constipation naturally:

  • Eat a high-fiber diet that includes whole wheat breads and cereals, vegetables, fruits and nuts.
  • Drink 8-10 glasses of water or other fluids a day.
  • Drink warm or hot fluids.
  • Exercise often. If exercise isn’t possible, tighten and relax the stomach muscles, and move the legs often while sitting in a chair or lying in bed.

Tell the doctor or nurse about irregular bowel movements. They may prescribe laxatives and stool softeners.


Chemotherapy and radiation (depending on the location targeted) can affect the cells lining your intestines and cause diarrhea. If diarrhea starts during a hospital stay, continues for more than 24 hours at home, and/or causes pain and cramping, tell the doctor or nurse. They may prescribe antidiarrheal medicine. Talk with a doctor before taking any over-the-counter antidiarrheal medicines.

The following may help control diarrhea:

  • Avoid:
    • Coffee, tea and alcohol
    • Fried, greasy or spicy foods
    • High-fiber foods such as whole grain breads and cereals; raw vegetables; beans, nuts, seeds and popcorn; and fresh and dried fruits
    • Milk and milk products (if they make the diarrhea worse)
    • Sweets
  • Eat more potassium-rich foods such as bananas, oranges, potatoes, avocados, peaches and apricots, unless your doctor tells you otherwise.
  • Eat smaller amounts of food, but eat more often.
  • Drink plenty of fluids to replace the ones you lost. Drink them slowly, and make sure they are at room temperature. Let carbonated drinks lose their fizz before drinking them.

For severe diarrhea, the doctor may prescribe a short-term clear liquid diet to give the bowels time to rest. A clear liquid diet includes water, apple juice, weak tea, clear broth or ginger ale, and gelatin. As you feel better, you can gradually add low-fiber foods. A clear liquid diet doesn’t provide all the nutrients you need, so don’t follow it for more than five days.

If your diarrhea is severe or lasts for many days, the doctor may order IV fluids to help replace the water and nutrients your body has lost.