INTRAVESICAL INSTILLATION OF OXYBUTYNIN IN WOMEN WITH IDIOPATHIC DETRUSOR INSTABILITY - A RANDOMIZED TRIAL

Urinary incontinence is one of the most socially incapacitating problems affecting women. Frequency, urgency and urge incontinence have been found to increase with age. Yet, no underlying cause has been established for the detrusor instability encountered in most patients. Oxybutynin chloride is a tertiary amine with combined anti-cholinergic, muscle relaxant and local anaesthetic properties (Diokno & Lapides 1972). Oral oxybutynin chloride has a well documented therapeutic effect in patients with bladder instability. However, the high incidence of anti-cholinergic side effects (30% to 80%) often requires dosage reduction or discontinuation of treatment (Brendler et al. 1989). Therefore, alternatives to conventional pharmacological treatment of detrusor instability have been the object of various studies (Brendler et al. 1989; Greenfield & Fera 1991). Intravesical drug instillation may be one such alternative. The aim of this study was to evaluate the benefits and side effects of intravesical oxybutynin application in women with idiopathic detrusor instability by means of a randomised, placebo-controlled trial.