Randomized, double-blind, placebo-controlled trial of polyethylene glycol (MiraLAX®) for urinary urge symptoms

Polyethylene glycol (PEG) is common first-line therapy for urinary symptoms despite minimal evidence-based support. We performed a randomized, double-blind, placebo-controlled study of PEG for initial treatment of overactive bladder (OAB) symptoms in children.

Patients aged >3 years underwent baseline urinary symptom questionnaire (USQ, scored 0-16), bowel symptom questionnaire (scored 0-20) and abdominal X-ray (KUB). Patients were randomized to placebo/PEG regardless of parent's perception of constipation. After 1 month, patients completed follow-up questionnaires and KUB. Improvement was defined as decrease in USQ (ΔUSQ) ≥ 3 points. Secondary analyses compared urinary and bowel symptoms to KUB.

Of 138 enrolled patients, 71 (51.4%) completed 1 month of therapy. Analyses of those randomized to placebo vs. PEG and non-completers demonstrated similar demographics, baseline symptoms, and KUB. Patients treated with placebo and PEG both had significant improvement in USQ scores (p < 0.0001). Patients treated with placebo and PEG responded similarly to placebo (ΔUSQ 3.7 vs. 3.4, p = 0.773), with improvement in nearly half (48.5% PEG vs. 44.7% placebo). There was no correlation between KUB and urinary or bowel symptoms.

Nearly 50% of patients with urinary urge symptoms treated with either placebo or PEG for 1 month had improvement in urinary symptoms. KUB did not correlate with baseline or follow-up urinary or bowel symptoms.