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CHAPTER 55   Bowel Movement Disorders
TOPICS   Introduction ~ Constipation ~ Diarrhea ~ Fecal Incontinence
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Fecal Incontinence

Fecal incontinence is the uncontrolled passage of bowel movements.

Losing control over bowel movements and becoming incontinent is humiliating for most people. Older people who become incontinent of stool (feces) often fear that others will view them as helpless and dependent. Fortunately, fecal incontinence can often be cured or controlled with treatment.


Fecal incontinence has a variety of causes. Some causes, such as sudden diarrhea from an infection, stroke, and injuries to the anus or spinal cord, can suddenly turn a continent person into an incontinent person. Other causes, such as constipation with impaction, rectal prolapse (protrusion of the inside lining of the rectum through the anus), dementia, and damage to nerves from diabetes, gradually interfere with control of bowel movements until incontinence develops. Once incontinence develops, it may resolve and not return. Alternatively, incontinence may persist but occur sporadically or persist and occur frequently.

Symptoms and Diagnosis

Fecal incontinence can range from a small amount of staining on underclothing to loss of a large amount of stool. When stool is lost, it may be entirely liquid, entirely solid, or a mixture of both.

A doctor examines the anus and rectum, checking the extent of sensation of the skin around the anus and how tightly the anus closes. The doctor usually examines the inside of the anus and rectum using either a very short rigid viewing tube (anoscopy) or a longer flexible viewing tube (sigmoidoscopy). If the cause remains unclear, more specialized tests may be needed. These tests include x-rays to determine how the rectum functions after a barium dye is instilled into it or measurements of nerve and muscle function of the anus and rectum (manometry).


If fecal incontinence is caused by impacted stool in the rectum, the impaction must be removed. Options for removal include the use of enemas or manual removal of the impacted stool with a gloved finger. Once the impaction is removed, the large intestine is emptied with laxatives or by drinking a polyethylene glycol-containing solution.

Treatment of fecal incontinence involves establishing a regular pattern of bowel movements that results in well-formed stools. Dietary changes often help. In people without impaction, adding foods with a high fiber content to the diet increases the bulk of stools and the regularity of bowel movements. If fecal incontinence is due to persistent diarrhea, the cause of the diarrhea is addressed. A drug that slows bowel movements, such as loperamide, may be beneficial.

Exercising the circular muscle that keeps the anus closed (anal sphincter) by squeezing and releasing it increases its tone and strength and helps prevent fecal incontinence from recurring. Biofeedback can help a person learn to control this muscle when a bowel movement is imminent. Biofeedback involves electrical monitoring and display of muscle contractions so that the person can directly observe muscle activity. Biofeedback can also improve the person's response to the presence of stool in the rectum. About 70% of motivated people benefit from biofeedback.

Surgery may benefit a small number of people—for instance, when the cause is an injury to the anal sphincter. As a last resort, a colostomy (the surgical creation of an opening between the large intestine and the abdominal wall) may be performed. The anus is sewn shut, and bowel movements are diverted into a removable plastic bag attached to an opening in the abdominal wall. A colostomy does not always have to be permanent.

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