Selecting a medical therapy for overactive bladder.

Immediate-release oxybutynin was the gold standard for pharmacologic treatment of overactive bladder for nearly 30 years. Intolerable systemic side effects, in particular dry mouth, limited its clinical utility, resulting in poor patient compliance with dosing regimens. Multiple studies have demonstrated the vastly superior tolerability of tolterodine, extended-release tolterodine, and extended-release oxybutynin over that of immediate-release oxybutynin at equivalent doses, and in the case of extended-release oxybutynin even to twice the dose of the original immediate-release form. With different drug delivery systems and, perhaps, with better bladder selectivity, these new oral agents have favorable side effect profiles, which translate into higher patient compliance and fewer treatment withdrawals or dosage reductions.