Causes Of Constipation - Constipation: Digestive Disorders

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Causes of constipation

There are many causes of constipation. Some can easily be prevented by changing habits and lifestyle; others have to do with physiological problems or diseases. Following are the more common causes of constipation:

Lack of exercise. People who exercise regularly seldom complain about constipation. Basically, the colon responds to activity. Good muscle tone in general is important to regular bowel movements. The abdominal wall muscles and the diaphragm all play a crucial role in the process of defecation. If these muscles are flabby, they're not going to be able to do the job as well. But exercise is not a cure-all. Increasing exercise to improve constipation may be more effective in older people, who tend to be more sedentary, than in younger people.

Medications. Constipation is a side effect of many prescription and over-the-counter drugs. These include pain medications (especially narcotics), antacids that contain aluminum, antispasmodics, antidepressants, tranquilizers and sedatives, bismuth salts, iron supplements, diuretics, anticholinergics, calcium-channel blockers, and anticonvulsants.

Irritable bowel syndrome (IBS). Some people who suffer from IBS (see "Irritable bowel syndrome") have spasms in the colon that affect bowel movements. Constipation may be the predominant symptom, or it may alternate with diarrhea; cramping, gas, and bloating are also common.

Abuse of laxatives. People who use laxatives for a long time often come to rely on them for both psychological and physiological reasons. The colon may begin to require laxatives to spur bowel movements. In the past, laxatives were thought to damage nerve cells in the colon and interfere with the colon's innate ability to contract. However, newer formulations of laxatives have made this outcome rare (see "Oral laxatives").

Changes in life or routine. Pregnancy, for example, may cause women to become constipated because of hormonal changes or because the heavy uterus pushes on the intestine. Aging often affects regularity because a slower metabolism can reduce intestinal activity and muscle tone. Traveling can give some people problems because it changes normal diet and daily routines.

Ignoring the urge. If you have to go, go. If you hold in a bowel movement, for whatever reason, you may be inviting a bout of constipation. People who repeatedly ignore the urge to move their bowels may eventually stop feeling the urge.

Not enough fiber in the diet. A diet too low in fiber (found in fruits, vegetables, and grains) and too high in fats (found in meats and cheeses) can contribute to constipation. Fiber absorbs water and causes stools to be larger, softer, and easier to pass. Increasing fiber intake helps cure constipation in many patients, but those with more severe constipation sometimes find that increasing fiber makes their constipation worse.

Not enough liquids. Water, juice, and other liquids add fluid to the colon and may make stools softer, but there is no evidence that increasing fluids will cure constipation. On the other hand, liquids containing caffeine can have a dehydrating effect that may be counterproductive, although some people say drinking coffee seems to help them move their bowels.

Other causes of constipation. Diseases that can cause constipation include neurological disorders, such as Parkinson's disease, spinal cord injury, stroke, or multiple sclerosis; metabolic and endocrine disorders, such as hypothyroidism, diabetes, or long-term kidney disease; bowel cancer; and diverticulitis (see "Diverticular disease"). A number of systemic conditions, like scleroderma, can also cause constipation. In addition, intestinal obstructions, caused by scar tissue (adhesions) from an operation or strictures of the colon or rectum, can compress, squeeze, or narrow the intestine and rectum, causing constipation.

Last updated:	August 21, 2007