Constipation is when you have difficulty passing stools and experience a decrease in the frequency of stools. Constipation can be accompanied by bloating, stomach cramps, or nausea. It is a chemo side effect that can often be managed by diet or by medication.

Your doctor will want to make sure that you are having regular bowel movements during chemotherapy (chemo). Chronic constipation can lead to something called stool impaction. This occurs when the stool gets stuck and cannot pass through the colon or rectum. Impaction can be a very serious complication of constipation. If it occurs, your doctor or other healthcare provider will need to remove the impacted stool.

Causes of Constipation

Constipation can have a number of causes, including:

  • Chemo medications
  • Medications given to reduce pain
  • Decreased physical activity
  • Not eating enough foods with fiber
  • Not drinking enough water or other fluids


Symptoms of constipation include:

  • Fewer bowel movements than what is normal for you
  • Hard, difficult-to-pass bowel movements
  • Cramping or stomach-ache
  • Flatulence (gas)

Prevention Tips

It is easier to prevent constipation with lifestyle changes than to treat it once it happens. Here are some tips:

  • Drink plenty of water. Fluids keep the stool soft.
  • Eat foods high in fiber; these include fruit, vegetables, and nuts.
  • If your doctor approves, exercise daily. Exercise helps stimulate digestion and prevent constipation. Even moderate activity, such as walking, will help.

Keep track of your bowel movement schedule so you can learn which lifestyle measures work best for you. If you miss a bowel movement, try increasing your fluid intake or adjusting your diet. Call your doctor if your bowels have not moved in 2 days; your doctor may choose to prescribe a laxative or other medication.


If you have tried the above lifestyle changes and still experience constipation, your doctor may prescribe laxatives. Laxatives are available in many forms, including tablets, gum, powder, granules, or a liquid.

Let your care team know if you have signs or symptoms of constipation. Ask your healthcare provider which type of laxative or stool softener will work best for you. As with all treatments, speak with your doctor and healthcare team about the risks and benefits of treatments for constipation.

Ask Your Doctor:

  • Is my chemo treatment likely to cause constipation?
  • What can I do to reduce constipation?
  • Are there treatments I can take to ease constipation? What are the risks and benefits of these treatments?
  • What foods should I avoid during chemo? What foods can help?
  • How long will my constipation last?
  • What do I do if I have not had a bowel movement in days?

 Print this worksheet 
 and bring it to your next doctor's visit.

A Closer Look: Zelda*
Feeling very confident about getting through chemo, Zelda meets regularly with a nutritionist recommended by her doctor.
She drinks a lot of fluids on her chemo treatment days and between chemo sessions.
She eats high-fiber foods as directed.
The week after receiving her fifth chemo treatment, Zelda starts to have cramps and constipation. After she is unable to move her bowels for 3 days, she calls her doctor.
Her doctor prescribes a laxative, which helps her.

*This is a fictional case study based on chemo patient experiences. Your experience is unique. Your doctor and care team will create a plan that will best treat your type of cancer and manage your chemo side effects.

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