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Chemotherapy Side Effects – Diarrhea

What it is and why it occurs

Diarrhea is frequent bowel movements that may be soft, loose, or watery. Chemotherapy can cause diarrhea because it harms healthy cells that line your large and small bowel. It may also speed up your bowels. Diarrhea can also be caused by infections or drugs used to treat constipation.

Ways to manage

  • Eat 5 or 6 small meals and snacks each day instead of 3 large meals.
  • Ask your doctor or nurse about foods that are high in salts such as sodium and potassium. Your body can lose these salts when you have diarrhea, and it is important to replace them. Foods that are high in sodium or potassium include bananas, oranges, peach and apricot nectar, and boiled or mashed potatoes.
  • Drink 8 to 12 cups of clear liquids each day. These include water, clear broth, ginger ale, or sports drinks such as Gatorade® or Propel®. Drink slowly, and choose drinks that are at room temperature. Let carbonated drinks lose their fizz before you drink them. Add extra water if drinks make you thirsty or nauseous (feeling like you are going to throw up).
  • Eat low-fiber foods. Foods that are high in fiber can make diarrhea worse. Low-fiber foods include bananas, white rice, white toast, and plain or vanilla yogurt. See the section on Low-Fiber Foods for other ideas.
  • Let your doctor or nurse know if your diarrhea lasts for more than 24 hours or if you have pain and cramping along with diarrhea. Your doctor may prescribe a medicine to control the diarrhea. You may also need IV fluids to replace the water and nutrients you lost. Do not take any medicine for diarrhea without first asking your doctor or nurse.
  • Be gentle when you wipe yourself after a bowel movement. Instead of toilet paper, use a baby wipe or squirt of water from a spray bottle to clean yourself after bowel movements. Let your doctor or nurse know if your rectal area is sore or bleeds or if you have hemorrhoids.
  • Ask your doctor if you should try a clear liquid diet. This can give your bowels time to rest. Most people stay on this type of diet for 5 days or less. See Clear Liquids for a list of clear liquids.

Stay away from:

  • Drinks that are very hot or very cold
  • Beer, wine, and other types of alcohol
  • Milk or milk products, such as ice cream, milkshakes, sour cream, and cheese
  • Spicy foods, such as hot sauce, salsa, chili, and curry dishes
  • Greasy and fried foods, such as French fries and hamburgers
  • Foods or drinks with caffeine, such as regular coffee, black tea, cola, and chocolate
  • Foods or drinks that cause gas, such as cooked dried beans, cabbage, broccoli, and soy milk and other soy products
  • Foods that are high in fiber, such as cooked dried beans, raw fruits and vegetables, nuts, and whole-wheat breads and cereals
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