Pediatric Hospital MedicineJournal Club

Moises Auron MD FAAP

February 19, 2009.

Summary• Very limited evidence base supporting the use of laxatives in

children • Systematic review

– RCT of polyethylene glycol (PEG) versus either placebo or active comparator

• Patients with primary chronic constipation. • Outcomes were global assessments of effectiveness or differences

in defaecation rates. • Seven studies (n = 594 children)• Five were comparisons of PEG with lactulose, one with milk of

magnesia and one with placebo.• PEG based treatments having been proven to be effective and• well-tolerated first-line treatment.

Constipation

• Experience of painful bowel movements

• Toilet training

• Changes in routine or diet

• Stressful events

• Intercurrent illness

• Delaying defaecation.

Constipation

Water reabsorption

Hard stools

Difficult and painful to pass

Faecal impactionRectum distentionDecreased urge

Faecal incontinence

• 75–80% of the weight of the normal stool – H2O

• A difference of only 10% will result in marked changes in stool consistency.

• PEG - water soluble polymer - form hydrogen bonds with 100 molecules of water per molecule of PEG (MW 3350).

• Colonic content hydration improved transit and painless defaecation

• Standard management of chronic constipation tends to begin with correction of dietary and lifestyle factors which predispose to the condition, in particular by increasing dietary fibre and fluid intake. However, dietary manipulation alone, including the use of corn syrup, was successful in resolving all symptoms of constipation in only 25% of children aged up to 2 years in one US study. Where simple measures fail, or where disimpaction is required, the next step involves one or more

Literature search

Study criteria

Discussion

• Improved evidence based information• Once disimpacted, even severely affected children can

be maintained satisfactorily on low doses of PEG• PEG can be used as monotherapy • 1/3 of patients on lactulose required senna• No patient on PEG+E reimpacted compared with almost

one in four on lactulose.• Different PEG doses - cannot necessarily assume

equivalence. • Different doses - titration vs. fixed dose• No clinical studies comparing PEG with PEG+E