Trospium chloride: an anticholinergic quaternary ammonium compound for the treatment of overactive bladder.

The International Continence Society has defined overactive bladder (OAB) as urinary urgency, with or without urge urinary incontinence, usually with urinary frequency and nocturia. Approximately 17% of men and women in the US report OAB symptoms, which can affect quality of life. Trospium chloride, which has recently been introduced in the US as Sanctura, has been prescribed for > 10 years in Europe as, for example, Spasmo-lyt, Regurin and Spasmex. Trospium chloride has been shown to be effective in relieving OAB symptoms, and has a favourable safety profile, showing < 1% difference for all adverse events compared with placebo, except for dry mouth, constipation and headache. Metabolic drug-drug interactions are unlikely, given that trospium chloride is not metabolised by cytochrome P450 isozymes. The fast-acting efficacy of trospium chloride, coupled with its good safety profile and tolerability, make it an important new option for treatment of OAB.