Encyclopedia / C / Constipation


What Is Constipation?

Constipation is more a complaint than a disorder—in fact, it is the most common gastrointestinal complaint in the United States. Constipation is characterized by infrequent bowel movements with stools that are often hard and sometimes painful to pass. The condition results when intestinal contractions slow down, allowing more time for the bowels to remove water from food wastes.

The normal frequency of bowel movements varies greatly from person to person—it is perfectly normal for some people to have three bowel movements a day, while others have as few as three a week. Constipation involves the passage of hard stools less than three times in a week, usually accompanied by bloating and discomfort. Any change in a person’s usual frequency of bowel movements, however, may be a sign of a more serious underlying disorder.

Constipation occurs frequently in infants and children, particularly when the diet is composed largely of highly refined foods. As with adults, bowel movement frequency in children varies tremendously—from several times a day to as little as once a week.

In most cases, constipation is not a serious condition. It usually can be treated with lifestyle measures—such as increasing your intake of dietary fiber and/or physical activity—or by taking a laxative.

Who Gets Constipation?

Constipation can stem from a number of medical conditions, including lower digestive tract disorders. Nearly everyone has had a bout of constipation—infrequent bowel movements and difficulty passing stool—at some point in their lives. In adults, constipation becomes more common with age and occurs in at least 25 percent of people over age 65.


  • Infrequent, difficult, and possibly painful bowel movements.
  • Straining during bowel movements.
  • Continued sensation of fullness after bowel movements.
  • Hard, dry stool.
  • Abdominal swelling, bloating.

Causes/Risk Factors

  • Lack of fiber in the diet or inadequate fluid intake.
  • Irregular or abnormal contractions of the bowel muscles resulting from a lack of exercise or disorders such as irritable bowel syndrome, diabetes mellitus, hypercalcemia, hypothyroidism, or colorectal cancer
  • Failure to empty the bowels when the urge strikes may lead to the formation of hard, impacted stool.
  • Overuse of laxatives, aspirin, or aluminum- or calcium-based antacids.
  • Certain medications, including antihypertensive drugs (calcium channel blockers and beta-blockers), tricyclic antidepressants, narcotics, and atropine.
  • Travel or other shift in your daily routine that changes your regular toilet habits.
  • Hormonal changes of pregnancy.

What If You Do Nothing?

If you have no other symptoms, constipation may clear up on its own in a matter of days; however, at the very least you may need to make some changes in your diet or other lifestyle habits to alleviate it.


Evaluation includes a medical history (with emphasis on bowel habits) and a physical exam. The physical exam often involves a digital rectal exam (DRE). In DRE, the physician inserts a lubricated, gloved finger into the patient's rectum to detect tenderness, blockage (e.g., colorectal polyp), or blood.

Diagnostic tests that may be performed include the following:

  • Blood and stool samples.
  • Anorectal function test to evaluate the function of the anus and rectum.
  • Barium enema (uses x-rays and a contrast solution to view the rectum, colon, and lower portion of the small intestine).
  • Colonoscopy or sigmoidoscopy (involve using a flexible tube with a light and camera attached to view the inside of the colon).
  • Colorectal transit study to evaluate how well food moves through the colon. (The patient swallows capsules containing markers that are visible on x-ray and a series of x-rays is taken 3 to 7 days later.)
  • Defecography (uses x-rays to evaluate how well stool is eliminated through the rectum and anus).


  • Eat a diet high in fiber—for example, whole grains (including unprocessed wheat bran), fruits, vegetables, and legumes
  • Drink plenty of nonalcoholic fluids to soften the stool—at least eight glasses a day
  • Drink a cup of hot liquid (such as coffee or tea), especially first thing in the morning, to activate what is known as the gastrocolic reflex, which induces a bowel movement by stimulating the colon
  • Get regular exercise and physical activity to strengthen your abdominal and pelvic floor muscles, which can stimulate bowel movements
  • Set aside regular bathroom time and try not to ignore the urge to defecate—even when it may not be convenient
  • Use laxatives only as a last resort and at the advice of your doctor. Bulk-forming agents, including bran, psyllium (Metamucil, Konsyl), and methyl cellulose (Citrucel, Cologel), are usually the best choice. Never use mineral oil as a laxative.
  • Do not use enemas, unless instructed to do so by your doctor.
  • Dietary changes usually relieve childhood constipation. Increase the child’s daily intake of fiber-rich food (whole grain products, fruits, and vegetables) and liquids. If the constipation stems from toilet training, stop the training and use diapers until the child actually has the urge to use a toilet.
  • If a medication you are taking for another health problem is the suspected cause of your constipation, your doctor may be able to lower the dosage of the drug or switch you to a medication that does not have constipation as a side effect. (Never stop taking a medication or change the dosage without first consulting your doctor.)
  • Severe chronic (i.e., long lasting) constipation can cause complications that may require additional treatment. Complications include hemorrhoids (dilated veins in the rectum), rectal prolapse (condition in which part of the lining of the rectum protrudes from the anus), anal fissures (small tears in the anus), and fecal impaction (condition in which stool is packed into the colon and cannot be expelled normally).


  • Eat high-fiber, low-fat foods. Try to get at least five servings a day of fiber-rich foods, including raw fruits and vegetables, whole-grain breads and cereals, bran, dried peas and beans, and potato skins.
  • Drink at least eight glasses of water a day.
  • Exercise regularly.
  • Empty your bowels as soon as possible when the urge strikes.

When To Call Your Doctor

  • Make an appointment with a doctor if constipation persists for two weeks or more, and increased fiber intake and exercise have failed to help.
  • Consult a doctor if fever or severe abdominal pain occurs with constipation; if abdominal bloating, cramping, or other discomfort disrupts your routine; and/or if you notice blood in the stool.
  • Call a doctor if you experience constipation shortly after beginning a new medication. The prescription may need to be adjusted.
  • Call your doctor if you notice any major change in your usual bowel habits.

Reviewed by Michael S. Soliman, M.D., family medicine physician in private practice and hospitalist at Mount Holyoke Medical Center, Mount Holyoke, MA.