Paediatrics: how to manage functional constipation

Despite being a common problem in childhood, functional constipation is often difficult to manage. This article provides a narrative updated review on the evaluation, diagnosis and management of childhood functional constipation.

A PubMed search was performed with Clinical Queries using the key term 'functional constipation'. The search strategy included clinical trials, meta-analyses, randomized controlled trials, observational studies and reviews. The search was restricted to the English literature and to the paediatric population. The information retrieved from the above search was used in the compilation of the present article.

A detailed history and thorough physical examination are important in the evaluation of a child with constipation to establish the diagnosis of functional constipation as per the Rome IV criteria and to catch 'red flags' suggestive of organic causes of constipation. These 'red flags' include delayed passage of meconium, ribbon stool, rectal bleeding/blood in the stool unless attributable to an anal fissure, failure to thrive, severe abdominal distension, absent anal wink/cremasteric reflex, tight and empty rectum on digital examination and explosive expulsion of liquid stool and gas on withdrawal of the finger, hair tuft/dimple/lipoma/haemangioma in the lumbosacral area, and an anteriorly displaced anus. For functional constipation, pharmacological therapy consists of faecal disimpaction and maintenance therapy. This can be effectively accomplished with oral medications, rectal medications or a combination of both. The most commonly used and most effective laxative is polyethylene glycol. Non-pharmacological management consists of education, behavioural modification and dietary interventions. The combination of pharmacological therapy and non-pharmacological management increases the chance of success.

Polyethylene glycol is the medication of first choice for both disimpaction and maintenance therapy. If polyethylene glycol is not available or is poorly tolerated, lactulose is the preferred alternative. Other laxatives may be considered as second-line therapy if treatment with osmotic laxatives fails or is insufficient. Maintenance treatment should be continued for at least 2 months. Early treatment will result in a faster and shorter treatment course.