Constipation

Constipation may be a symptom of disease in the lower bowel, most commonly irritable colon or diverticular disease. Cancer is also a possibility, though it is likely to be of recent onset and associated with other symptoms such as diarrhea or bleeding. Constipation is occasionally due to a lack of coordination between an attempt to empty the bowel and the contracted sphincter muscles and the puborectalis, which fail to relax appropriately. Another possible cause is trauma in the anal canal—such as a fissure or painful hemorrhoids—which can result in an individual avoiding defecation. Management of all these conditions requires medical investigation and appropriate treatment.

Constipation may also be caused by a number of medications that increase shuttling motility. Figure 3 Loss of ano-rectal angle due to constipating mass of feces in the rectum. SOURCE: Author These include morphine and its derivatives, especially codeine, or drugs that prevent mass peristalsis, such as other antidiarrhea drugs. The character of the diet (especially if it becomes low in bulky and fibrous foods such as vegetables) may cause constipation. Other causes include a change of living conditions (e.g., moving into a communal living environment), a toilet that is not easily accessible, and a loss of the ability to walk far, and constipation may be associated with a number of general diseases such as depression, hypothyroidism, and diabetes.

The most common cause of constipation, however, is called dyschezia, or ideopathic constipation (ideopathic means that the cause is unknown). This condition occurs at all ages and is not necessarily associated with aging. Various life-long and lifestyle features may be responsible, including inappropriate toilet training or possible abuse in childhood; deliberate suppression of defecation over a long period in situations that are perceived as embarrassing; lack of exercise; a diet low in fiber; or overuse of laxatives. Counseling and explanation may be sufficient in managing dyschezia. Occasionally, keeping a diary of bowel motions, measuring transit time (e.g., time for a number of swallowed markers to appear in the feces), and the exclusion of diseases mentioned above are required. Correction of diet and exercise are important, and laxatives may be used with discretion (see below).