Oncology: Controlling Constipation

Difficulty passing stool (constipation) is a common side effect of cancer treatment. Constipation is when you have any of the following:

  • You aren't moving your bowels like you usually do

  • You feel like you need to move your bowels, but can't

  • You have trouble passing small, dry, hard stools.

It can be caused by many different things, such as:

  • Chemotherapy

  • Pain medicine

  • Other medicines you may be taking

  • Diet changes

  • Decreased fluid intake

  • Decreased physical activity

Constipation can cause bloating or fullness, gas, belly cramps, nausea, vomiting, and take away your desire to eat. In severe cases, liquid stool that looks like diarrhea may leak around the hard stool that's blocking your bowel.

Man and woman outdoors, walking.

3 steps to help treat constipation

The best way to treat constipation is to keep it from happening. Ask your healthcare provider if you are at risk for constipation and what you should do to try to prevent it. These steps can help:

Step 1. Drink plenty of fluids

Water, prune juice, and warm or hot drinks are good choices. Try drinks that have worked for you in the past.

Step 2. Eat high-fiber foods

Whole grains, nuts, bran, fruit, and vegetables all can help prevent constipation by increasing stool bulk, making it easier to pass. Ask your provider if it's OK to add more fiber to your diet and how to do it.

Step 3. Exercise often

It's important to be up and moving. Taking a short walk each day is a good way to start. Check with your provider before starting an exercise program.

When to see your healthcare provider

Contact your healthcare provider if:

  • You have no bowel movement in 3 days or more, especially if you are taking vinca alkaloids (vinblastine, vincristine, or vinorelbine) or pain medicine

  • You are vomiting

  • You have pain in your belly

  • You see blood when you wipe or there's blood in your stool

  • The laxative you were instructed to use doesn't work in a day or 2

Medicines can also help

Ask your healthcare provider about medicines to help manage constipation. Your provider may prescribe a stool softener or laxative. These can relieve constipation by helping you have a bowel movement. You may also be told to take them daily for a while to help keep you from becoming constipated again. Don't take any over-the-counter product without asking your provider first.