Darifenacin for the Treatment of Overactive Bladder

Abstract

Overactive bladder is a debilitating disorder affecting 16.5% of adults and increasing in prevalence with age. Symptoms, including urgency, urge incontinence and frequency can result from detrusor overactivity with contraction of the bladder mediated primarily by activation of muscarinic M 3 receptors. Antimuscarinic agents are therefore an important approach to treating overactive bladder, but a lack of M 3 receptor subtype selectivity with these agents can generate a range of side effects that limits their effectiveness. This review describes an alternative approach to treating overactive bladder using the selective muscarinic M 3 receptor antagonist darifenacin. The M 3 receptor selectivity of darifenacin improves the symptoms of overactive bladder while reducing the potential for deleterious effects of non-M 3 muscarinic receptor antagonism in the brain or heart. The pharmacology and pharmacokinetics of darifenacin are summarized, and the its clinical efficacy and demonstrated safety profile are described.