Constipation refers to infrequent bowel movements or difficulty passing stool. There are many causes of constipation. Most commonly, it is due to a slow transit of fecal material through the colon. This may be related to diet, inactivity, medication side effects or other underlying medical conditions. Constipation may also result from a physical blockage of the intestine, such as colorectal cancer. It may also arise from problems with evacuating the rectum due to disorders of the anal or rectal nerves and muscles.
Symptoms of constipation include abdominal bloating and distention, infrequent bowel movements, passage of hard stool and difficulty evacuating the rectum.
The diagnosis is typically made based on the patient’s symptoms and a description of their bowel habits. Laboratory tests are often ordered to rule out underlying medical conditions, such as hypothyroidism or electrolyte abnormalities. An x-ray examination of the colon or a colonoscopy may be necessary to prove that there is not a mechanical obstruction of the colon. Rarely, more sophisticated testing such as anorectal manometry is necessary to eliminate disorders of the nerves and muscles of the rectum and anus.
Constipation can often be relieved simply by increasing fluid and fiber intake. Occasionally, laxatives are necessary to allow adequate elimination. Exercise and a healthy lifestyle will also contribute to more normal bowel function.