ABSTRACT
Patients with idiopathic constipation are usually physically fit and have no evidence of illness except for the soiling of underwear that occurs in some children. Idiopathic constipation may be present at birth but the parents may not notice the symptoms until much later, usually at the time of toilet-training. The history of delayed passage of meconium is commonly encountered in children with Hirschsprung's disease. Such children present with constipation because they have been passing faeces through a narrow orifice. Their physical examination, except for the perineum, is otherwise unremarkable. The appropriate treatment is disimpaction, which may be achieved with potent enemas, a bowel clean-out and/or manual evacuation under anaesthesia. Giving the patient laxatives in the presence of faecal impaction leads to exacerbation of the abdominal pain, severe cramping and sometimes vomiting. This is a consequence of an increased colonic peristalsis produced by laxatives that acts against the colonic obstruction from impaction.
