This is a prospective, randomized controlled clinical trial designed to compare the efficacy and safety of transdermal versus oral oxybutynin in children diagnosed with overactive bladder (OAB) who remain symptomatic despite conservative management. A total of 90 children were planned to be enrolled and randomized to receive either oral oxybutynin suspension or a transdermal oxybutynin patch. The primary outcome was defined as the change in Dysfunctional Voiding and Incontinence Symptom Score (DVISS) from baseline to the end of the treatment period. Secondary outcomes included changes in urinary frequency, voided volume, maximum flow rate (Qmax), and the incidence of adverse events. The study aimed to assess whether the transdermal route of administration provides an alternative therapeutic option with favorable tolerability in pediatric OAB patients.

Inclusion Criteria:

• Persistent symptoms of overactive bladder (OAB) despite at least 3 months of conservative treatment (e.g., behavioral therapy, planned fluid intake, and voiding schedules)
• No prior medical or surgical treatment for OAB
• Ability to attend follow-up visits with family/guardian
• Written informed consent obtained from a legal guardian

Exclusion Criteria:

• History of febrile or recurrent urinary tract infections
• Presence of urethral stricture
• Known or suspected neurogenic bladder dysfunction
• Previous bladder surgery
• History of urolithiasis (kidney stones)
• Contraindications to oxybutynin therapy