Intravesical atropine compared to oral oxybutynin for neurogenic detrusor overactivity: A double-blind, randomized crossover trial

Purpose: We tested the efficacy and side effect profiles of intravesical atropine compared to oxybutynin immediate release when used by individuals with multiple sclerosis. Materials and Methods: We performed a study to determine the most effective dose of atropine. Eight participants used increasing doses of intravesical atropine during a 12-day period. Bladder diary data showed that the instillation of 6 mg atropine 4 times daily was most effective for increasing bladder capacity (voided/catheter volumes). We then did a randomized, double-blind crossover trial. Participants received 14 days of treatment with oral oxybutynin or with intravesical atropine, followed by 14 days of alternative treatment. Participants recorded a bladder diary and rated side effects and quality of life. The primary outcome variable was bladder capacity. Results: A total of 57 participants with multiple sclerosis completed the study. Average change in bladder capacity was higher in the atropine arm. The mean +/- SD oxybutynin change was 55.5 +/- 67.2 ml, the mean atropine change was 79.6 +/- 89.6 ml and the mean difference between arms was 24.1 ml (95% CI -0.4, 49.7; p = 0.053). Changes in incontinence events and voiding frequency were not statistically different between the arms. Changes in total side effect and dry mouth scores were significantly better in the atropine treatment arm. Conclusions: Intravesical atropine was as effective as oxybutynin immediate release for increasing bladder capacity and it was probably better with less antimuscarinic side effects. We recommend that intravesical atropine should be made available to patients with neurogenic detrusor overactivity and voiding problems requiring intermittent catheterization as an alternative to oral therapy, which often has troublesome side effects.