Encopresis, often called fecal soiling or overflow incontinence in adults, is the involuntary passage of stool into clothing after the age of toilet training. This condition is a physical symptom resulting from a severe disruption in normal bowel function, not a failure of hygiene or will. Addressing adult encopresis requires understanding the underlying physical mechanism, distinct causes, and a structured treatment approach.
Understanding the Mechanism of Adult Encopresis
The physical process behind adult encopresis is linked to chronic, severe constipation resulting in fecal impaction. When stool remains in the colon and rectum for a prolonged period, the colon absorbs excessive water, causing the feces to become hard and massive. This hardened mass, known as a fecal impaction, obstructs the rectum and is too large to pass normally.
This prolonged distention of the rectum stretches and desensitizes the nerves responsible for sensing the urge to defecate. The constant pressure on the internal anal sphincter causes it to relax permanently. Liquid or semi-liquid stool produced higher up in the colon then leaks around the impacted, solid mass, resulting in involuntary soiling, known as overflow incontinence.
Encopresis is characterized by a hard, unpassed stool mass acting as a dam, with liquid stool bypassing the obstruction. This differs from general fecal incontinence, which results from nerve or muscle damage and occurs independently of impaction. Mistaking the overflow for diarrhea can lead to inappropriate anti-diarrheal treatment, worsening the underlying impaction.
Primary Causes and Contributing Risk Factors
The root cause of adult encopresis is chronic constipation leading to fecal impaction, which is often multifactorial. Common contributors include a diet low in fiber and insufficient fluid intake, which slows intestinal transit time and hardens the stool. Additionally, a sedentary lifestyle or reduced mobility significantly decreases the peristaltic action necessary to move waste through the bowel.
Medication side effects represent a frequent risk factor. Opioid pain medications are particularly notorious, as they directly slow gut motility and decrease intestinal secretions, leading to severe opioid-induced constipation. Other common culprits include anticholinergic drugs, such as certain antidepressants and medications used to treat overactive bladder, which block nerve signals regulating bowel movement.
Underlying neurological and systemic conditions can also impair the bowel’s ability to function correctly. Conditions like Parkinson’s disease, multiple sclerosis, and spinal cord injuries can damage the nerves controlling the colon and rectum, altering colonic transit time and sphincter function. Ignoring the urge to defecate, often due to pain from a previous hard stool or lack of convenient toilet access, can also create a long-term behavioral cycle of retention that stretches the rectum and causes chronic impaction.
Medical Assessment and Diagnosis
The diagnostic process begins with a detailed patient history and physical examination to establish the presence of chronic constipation and soiling episodes. A healthcare provider typically performs a digital rectal examination (DRE) to manually check for a hard, impacted mass in the rectum, a definitive sign of the condition. This exam also assesses the strength and resting tone of the anal sphincter muscles.
To objectively confirm the extent of stool burden, an abdominal X-ray may be ordered. This imaging technique visualizes the amount of retained feces, helping to quantify the severity of the impaction and guide the initial disimpaction strategy.
If soiling persists after impaction is cleared, or if nerve or muscle dysfunction is suspected, specialized testing may be necessary. Anorectal manometry measures the strength of the anal sphincter muscles and the sensitivity of the rectum. This test helps determine if the issue is solely impaction-related or if an underlying defecatory disorder is present.
Step-by-Step Management and Treatment Strategies
Treatment for adult encopresis follows a structured, multi-phase approach, beginning with the removal of the retained fecal mass. Disimpaction is achieved through high doses of oral osmotic laxatives, such as polyethylene glycol, administered over several days to soften and evacuate the stool. In severe cases, rectal treatments like enemas or suppositories may be necessary to manually clear the lower impaction.
Once the bowel is clear, the focus shifts to a long-term maintenance regimen to prevent recurrence. This phase involves the daily use of laxatives, often osmotic agents, adjusted to ensure the passage of two to three soft, formed stools per day. Dietary modifications are simultaneously implemented, requiring a substantial increase in daily fiber intake and adequate fluid consumption to keep the stool soft.
Bowel retraining is implemented to restore the normal reflex for defecation. This behavioral component involves a scheduled toileting regimen, where the individual sits on the toilet for 5 to 10 minutes, typically 20 to 30 minutes after a meal. This timing takes advantage of the gastrocolic reflex, which assists in moving stool toward the rectum following eating.
Addressing any identified underlying causes is necessary for long-term success. This may involve collaborating with the prescribing physician to adjust or switch constipating medications. For individuals with a diagnosed defecatory disorder, biofeedback therapy may be recommended; this specialized training uses cues to help the patient learn to coordinate their pelvic floor muscles correctly during a bowel movement.