Overactive bladder (OAB), a common condition affecting ≊16–17% of adult men and women in Europe and the US, is characterized by symptoms of urinary urgency, with or without urge urinary incontinence (UUI), usually with micturition frequency and nocturia. OAB is thought to result from abnormal, involuntary detrusor contractions during bladder filling. The symptoms of OAB have a considerable adverse effect on quality of life (QOL) in affected patients, and are associated with an increased risk of comorbidities, and increased direct and indirect costs.Management of OAB focuses on symptom improvement, and includes nonpharmacologic and pharmacologic therapy. Extended-release tolterodine (Detrusitol®XL, Detrol LA®, Detrusitol SR®, Detrusitol®Neo, Detrusitol®Retard, Unidet™) is an oral, once-daily, nonselective, competitive antimuscarinic drug. It acts on smooth muscle motor efferent pathways, including bladder detrusor muscle, and is a first-line therapy for OAB. Extended-release tolterodine is at least as effective as immediate-release tolterodine in improving UUI and other symptoms associated with OAB (including urinary frequency, urgency symptoms, voided volume/micturition), and in improving health-related QOL. It has similar efficacy to oral immediate- or extended-release oxybutynin, or transdermal oxybutynin.The likelihood of dry mouth, the most bothersome anticholinergic adverse effect associated with antimuscarinic drugs, is significantly reduced with extended-release tolterodine in patients with OAB compared with immediate-release tolterodine. Dry mouth also occurs significantly less frequently with extended-release tolterodine than with immediate- or extended-release oxybutynin. The incidence of dry mouth with extended-release tolterodine or transdermal oxybutynin is similar.In economic models, extended-release tolterodine is more cost effective in patients with OAB than no treatment, or treatment with immediate-release tolterodine or immediate-release oxybutynin, and is as cost effective as extended-release oxybutynin.In conclusion, clinical and economic data support the use of extended-release tolterodine as a first-line therapy in the management of adult patients with OAB. It is at least as effective as immediate-release tolterodine, but is associated with a lower incidence of dry mouth. Moreover, the convenient once-daily administration regimen offers the potential for good compliance. The favorable efficacy and tolerability profile of extended-release tolterodine has been demonstrated for up to 12 months. Extended-release tolterodine is as effective as oral immediate- or extended-release oxybutynin, but is better tolerated in terms of dry mouth. It has similar efficacy and tolerability (including dry mouth) to transdermal oxybutynin. Extended-release tolterodine is, therefore, a valuable first-line therapy in the treatment of OAB.