Soiling is one of the most distressing — and least talked-about — problems in childhood. Parents are embarrassed. Children are deeply ashamed. Teachers may be exasperated. And the response most likely to make everything worse — anger and punishment — is often the first instinct, because the soiling looks deliberate.
It almost never is. In the vast majority of children, soiling is the result of chronic constipation and overflow incontinence: a rectum so packed with impacted stool that soft material bypasses the blockage and leaks into the underwear. The child genuinely does not feel it coming. Understanding this changes the entire approach.
Healthbooq (healthbooq.com) covers digestive health in children through the early years.
Why Soiling Happens
The most common mechanism is retentive soiling, also called overflow incontinence. A child becomes constipated — often after an illness, a dietary change, a stressful period, or an episode of painful defecation that triggered fear of the toilet. They begin to withhold stool, sometimes consciously and sometimes as an automatic reflex to avoid anticipated pain.
With repeated withholding, the rectum fills with hard, impacted stool. The rectal wall stretches to accommodate the increasing load. Over time, the muscle becomes overstretched and fatigued, losing normal tone. The stretch receptors that would normally signal "time to go" become blunted by constant distension. Soft, newer stool arriving from above can't get past the blockage and leaks around it — appearing in underwear as loose or liquid soiling, which is often mistaken for diarrhoea.
This is why the child genuinely cannot feel it coming: the sensation system has been overwhelmed by the chronic distension. What looks like deliberate soiling is physiologically impossible for the child to control.
Non-retentive soiling without underlying constipation is much less common and may relate to incomplete toilet training, psychological factors, or — rarely — neurological issues.
How Common It Is
Encopresis affects approximately 1 to 3 per cent of children over age four. It is roughly four times more common in boys than girls. The emotional toll is substantial: most affected children describe shame, social withdrawal, and significant anxiety around school and social situations. Bullying related to soiling is common. Studies of children with chronic encopresis show higher rates of depression and anxiety than the general paediatric population — though it's not always clear which came first.
Diagnosis
A GP will take a history covering stool frequency and consistency (using the Bristol Stool Scale as a reference), diet, fluid intake, and the pattern of soiling — timing, whether the child is aware of it, the consistency of what appears in underwear. NICE guideline NG90 provides the framework for assessment and management.
On examination, the abdomen may show palpable faecal masses — you can often feel the stool sitting in the colon. Digital rectal examination is rarely necessary in primary care when the history clearly points to constipation.
Overflow incontinence is distinguished from true diarrhoea by the history: the child is not having frequent watery stools. They are typically having infrequent hard stools — or no obvious stool at all — with liquid leakage between evacuations.
Hirschsprung's disease (a congenital absence of ganglion cells in the rectum causing obstruction) is important to exclude in children with severe constipation from infancy. It is usually identified in the newborn period but occasionally presents later with chronic severe constipation without overflow.
Treatment: Three Phases
NICE NG90 describes a structured three-phase approach.
Phase 1: Disimpaction. The backlog must be cleared before anything else can work. This is done with escalating doses of macrogol (polyethylene glycol — Movicol or Laxido in the UK), given over several days to weeks. The dose is increased until the child passes loose, clear stool — the signal that the impaction has cleared. Starting maintenance laxatives without disimpaction first is ineffective: the hard blockage remains and the soft stool continues to overflow around it.
The disimpaction phase is often uncomfortable and can be distressing for families, because the child may initially soil more as the blockage begins to move. This is expected and temporary.
Phase 2: Maintenance. After disimpaction, a lower daily dose of macrogol is continued — indefinitely, for months to years — to keep stool soft and the bowel moving regularly. This is where most families go wrong: they stop the laxative when soiling improves (usually after a few weeks), before the rectum has had adequate time to regain normal tone and sensation. The result is predictable: constipation returns, the rectum re-impacts, and the soiling restarts.
Most children need 12 to 24 months of maintenance treatment before the bowel has genuinely recovered. This feels like a long time. It is also what the evidence supports.
Phase 3: Behavioural support. Regular toilet sits after meals (making use of the gastrocolic reflex — the normal increase in colonic activity that follows eating), a positive and non-shaming approach at home and school, reward charts for sitting on the toilet rather than for outcomes, and clear communication with school so the child can access toilets freely without asking permission. Children with encopresis should never have to request permission to use the toilet.
The Role of Shame
Shame is the enemy of recovery. Children who are scolded, punished, or humiliated for soiling develop heightened toilet anxiety, become less likely to report accidents, begin hiding soiled underwear, and have worse outcomes across the board. Research comparing outcomes in children with encopresis consistently finds that shame and punishment are associated with prolonged recovery.
The most powerful thing a parent can do — alongside medical treatment — is to communicate clearly and calmly, over and over, that this is a medical problem and not the child's fault, and that the family will work on it together. This is harder than it sounds when you've been managing soiling for months. But it matters more than almost anything else in the treatment.
Key Takeaways
Encopresis is the passage of stool in inappropriate places in a child aged four or over who has been or should have been toilet trained. Around 90 per cent of cases are caused by overflow incontinence secondary to chronic constipation: the rectum becomes so distended with impacted stool that soft stool leaks around the blockage without the child being aware. It is not wilful or deliberate. Treatment involves disimpaction (clearing the backlog), followed by prolonged maintenance laxative therapy and behavioural support. Recovery takes months to years. Parental understanding that soiling is a medical symptom, not naughty behaviour, is crucial to avoiding shame that worsens outcomes.
