Evidence for the efficacy and safety of tolterodine in the treatment of overactive bladder.

Overactive bladder (OAB) is a chronic and prevalent condition, the symptoms of which (urinary frequency and urgency, with or without urge incontinence) can exert a profound negative effect on a person's daily life activities. Tolterodine (Detrol in North America and Detrusitol in the rest of the world, Pharmacia), a competitive muscarinic antagonist, is the first agent of this class to be specifically developed for the treatment of OAB. This agent displays in vivo functional selectivity for the bladder over other tissues that contain muscarinic receptors (e.g., salivary glands, eye), which translates into good efficacy and tolerability in patients with OAB (including the elderly). Comparative, randomised, double-blind studies show that tolterodine (administered as immediate-release [IR] tablets 2 mg b.i.d.) is as effective as oxybutynin (5 mg t.i.d.) in improving all of the troublesome symptoms of OAB but with a significantly lower incidence and severity of dry mouth. The advent of a new extended-release (ER) capsule formulation of tolterodine (4 mg) for convenient once-daily treatment builds upon these findings, with significantly improved efficacy for reducing urge incontinence episodes and a lower frequency of dry mouth relative to the existing IR tablet (2 mg b.i.d.). Tolterodine can therefore be considered a valuable, well-tolerated treatment option for patients with OAB, providing improvements in symptoms that are both clinically meaningful to patients and sustained during long-term treatment.