A dose determination study of polyethylene glycol 4000 in constipated children: factors influencing the maintenance dose.

Objectives: To determine the doses of polyethylene glycol (PEG) 4000 without additional salts allowing normal bowel habits in childhood functional constipation.

Methods: This multicenter noncomparative study allocated children to 4 groups: 6-12 months, 13 months-3 years, 4-7 years, and 8-15 years. Constipation was defined as <1 stool/d for more than 1 month in children aged 6-12 months and <3 stools/w for more than 3 months in older children. Children randomly received either a nominal or a double starting dose. Treatment scheduled for 3 months could be adapted. Data were collected daily by the parents and rated at each visit by the investigator.

Results: In the 96 children included, the median (interquartile) effective daily doses were by groups; 3.75 (2.50-5.00) g, 6.00 (4.00-7.43) g, 11.71 (7.00-16.00) g, and 16.00 (16.00-24.00) g, respectively, i.e., around 0.50 g/day/kg with a potential increment of the maintenance dose with higher initial dosages. More children had a final dosage identical to the initial one when started on the nominal dose (73%) than with the double one (42%, P < 0.003). More than 90% of children recovered normal bowel habits. Fecal soiling ceased in >60% of children with this symptom at enrolment. Fecal mass in the rectum and abdominal pain were markedly reduced and appetite improved.

Conclusions: A daily dose of PEG 4000 around 0.50 g/day/kg in children aged 6 months to 15 years is effective in more than 90% of constipated children and 60% of those with fecal soiling.