A randomized controlled trial of polyethylene glycol 4000 without electrolytes versus milk of magnesia for the treatment of functional constipation in infants and young children

Objective: To compare 2 laxatives, polyethylene glycol 4000 without electrolytes (PEG) and milk of magnesia (MOM). Evaluating the effectiveness, adverse effects and patient compliance. Study design: Randomized controlled trial Setting: Pediatric outpatient clinic, Bhumibol Adulyadej Hospital Methods: Infants and young children aged 1-4 years who met the Rome III criteria for functional constipation were randomly allocated to the PEG treatment group or MOM group. The primary outcome was the improvement rate. Secondary outcomes included the improvement of stool frequency, adverse effects and compliance rate. All outcomes were evaluated after 4 weeks of treatment. Results: 94 patients were enrolled. A total of 89 patients completed the study: 46 in the PEG group and 43 in the MOM group. Baseline characteristics including age, body weight, sex, initial stool frequency and duration of constipation were similar between groups. At the 4 week follow-up visit, 91% of PEG treated patients and 65% of the MOM treated patients exhibited improvement (p=0.003). Patients in the PEG group had greater increase of stool frequency after treatment than patients in the MOM group. Overall adverse effects were mild, transient and not different among groups, except there was more diarrhea in MOM treated patients. No serious adverse effects occurred. Compliance rates were 89% for PEG and 72% for MOM (p=0.041). Conclusion: In this randomized trial, PEG was more effective and had greater patient compliance than MOM for the management of functional constipation in infants and children aged 1-4 years.