Constipation

Description and Causes

Common factors that may cause constipation in healthy people are eating a low-fiberdiet, postponing visits to the toilet, using laxatives and enemas excessively, not drinking enough fluids, and exercising too little. In persons with cancer, constipation may be a symptom of cancer, a result of a growing tumor, or a result of cancer treatment. Constipation may also be a side effect of medications for cancer or cancer pain and may be a result of other changes in the body (organ failure, decreased ability to move, and depression). Other causes of constipation include dehydration and not eating enough. Cancer, cancer treatment, aging, and declining health can contribute to causing constipation.

More specific causes of constipation include:

Medications

• Chemotherapy treatments.
• Pain medications, including opioids.
• Medications for anxiety and depression.
• Stomach antacids.
• Diuretics.
• Vitaminsupplements such as iron and calcium.
• Sleep medications.
• General anesthesia.

Diet

• Not drinking enough water or other fluids.

Changed Bowel Habits

• Repeatedly ignoring the urge to pass stool.
• Using too many laxatives and enemas.

Immobility and Lack of Exercise

• Spinal cord injury, spinal cord compression, bone fractures, fatigue, weakness, long periods of bedrest.
• Inability to tolerate movement and exercise due to respiratory or cardiac problems.

Bowel Disorders

• Irritable colon.
• Diverticulitis.
• Tumor.

Muscle and Nerve Disorders (nerve damage can lead to loss of muscle tone in the bowel)

• Brain tumors.
• Spinal cord compression from a tumor or other spinal cord injury.
• Stroke or other disorders that cause muscle weakness or movement.
• Weakness of the diaphragm or abdominal muscles making it difficult to take a deep breath and push to have a bowel movement.

Body Metabolism Disorders

• Under-secretion of the thyroid gland.
• Increased level of calcium in the blood.
• Low levels of potassium or sodium in the blood.
• Diabetes with nervedysfunction.

Environmental Factors

• Needing assistance to go to the bathroom.
• Being in unfamiliar surroundings or a hurried atmosphere.
• Living in extreme heat leading to dehydration.
• Needing to use a bedpan or bedside commode.
• Lack of privacy.

Assessment of Constipation

A medical history and physical examination can identify the causes of constipation. The examination may include a digital rectal exam (the doctor inserts a gloved, lubricated finger into the rectum to check for stool impaction) or a test for blood in the stool. If cancer is suspected, a thorough examination of the rectum and colon may be done with a lighted tube inserted through the anus and into the colon. The following questions may be asked:

• What is your normal bowel pattern? How often do you have a bowel movement? When and how much?
• When was your last bowel movement? What was it like (how much, hard or soft, color)? Was there any blood?
• Has your stomach hurt or have you had any cramping, nausea, vomiting, pain, gas, or feeling of fullness near the rectum?
• Do you use laxatives or enemas regularly? What do you normally do to relieve constipation? Does this usually work?
• What kind of food do you eat? How much and what type of fluids do you drink daily?
• What medicine are you taking? How much and how often?
• Is this constipation a recent change in your normal habits?
• How many times a day do you pass gas?

Treatment

Treatment of constipation includes prevention (if possible), elimination of possible causes, and limited use of laxatives. Constipation caused by opioid pain medicine may be treated with a drug given by injection. Suggestions for the patient's treatment plan may include the following:

• Keep a record of all bowel movements.
• Increase the fluid intake by drinking eight 8-ounce glasses of fluid each day (patients who have kidney or heart disease may need to limit fluid intake).
• Exercise regularly, including abdominal exercises in bed or moving from the bed to chair if the patient cannot walk.
• Increase the amount of dietary fiber by eating more fruits (raisins, prunes, peaches, and apples), vegetables (squash, broccoli, carrots, and celery), 100% whole grain cereals and breads, and bran. Patients must drink more fluids when increasing dietary fiber or they may become constipated. (See the PDQ summary on Nutrition in Cancer Care for more information.) Patients who have had a bowel obstruction or have undergone bowel surgery (for example, a colostomy) should not eat a high-fiber diet.
• Drink a warm or hot drink about one half-hour before the patient's usual time for a bowel movement.
• Provide privacy and quiet time when the patient needs to have a bowel movement.
• Help the patient to the toilet or provide a bedside commode instead of a bedpan.
• Take only medications prescribed by the doctor.
• Do not use suppositories or enemas unless ordered by the doctor. In some cancer patients, these treatments may lead to bleeding, infection, or other harmful side effects.

Current Clinical Trials

Check NCI's list of cancer clinical trials for U.S. supportive and palliative care trials about constipation, impaction, and bowel obstruction that are now accepting participants. The list of trials can be further narrowed by location, drug, intervention, and other criteria.

General information about clinical trials is also available from the NCI Web site.