This study was performed evaluate optimal dose for disimpaction, efficacy and safety of PEG 4000 in children with chronic functional constipation.

Eighty six children with chronic functional constipation were enrolled in this prospective study at Konkuk university hospital March, 2003 through August, 2006. Success in disimpaction with PEG 4000 was defined as meeting at least two out of three criteria; resolution of chief complaint, getting easiness of defecation with respect to frequency of bowel movement and hardness of stool based on defecation diary, and decrease in fecal impaction on simple abdominal X-ray test. Adverse effects of PEG 4000 were monitored clinically and biochemically.

Eighty three out of 86 children completed the study, and success rate of disimpaction was 99% (82/83). The mean dose of PEG 4000 for disimpaction was 0.93±0.28 g/kg/day (0.4-2.0 g/kg/day, Max.: 30 g/day). Frequency of bowel movement increased (5.02±2.71/wk vs. 11.25±5.43/wk) in most children (79/83). Fecal impaction on simple abdominal X-ray test improved with statistical significance in 25 children ( P =0.0007). Because of adverse effect of PEG 4000, 3 children did not complete the study; urticaria, severe diarrhea, diarrhea and abdominal pain. One 6-year-old girl who completed the study complained tingling sensation in the hand and foot without laboratory abnormality (4/86, 4.7%). Laboratory test revealed hyperosmolality without clinical symptom in 1 child, and eosinophilia in 6 children.

The average safe and effective dose of PEG 4000 for disimpaction was 0.93±0.28 g/kg/day (0.4-2.0 g/ kg/day, Max:30 g/day) in children with chronic functional constipation.