Overactive bladder (OAB) is a common problem whose prevalence increases with advancing age and compromises health-related quality of life. Tolterodine was the first antimuscarinic drug specifically designed to treat OAB. Through MEDLINE, we reviewed articles, standardization reports and meeting abstracts, published between 2001 and 2011, on the efficacy and tolerability of Tolterodine extended release (ER). Our search terms included Tolterodine, extended release, overactive bladder, therapeutic use, efficacy, tolerance, and adverse events. Tolterodine ER, via steady drug release during the daytime, gives the benefit of constant serum concentration and thus better efficacy and tolerability in comparison to Tolterodine immediate release, even in elderly patients with co-morbid conditions.