Capsaicin is known to be neurotoxic for C-fiber afferents. We investigated the intravesical application of
capsaicin in the treatment of detrusor
hyperreflexia (DH) in seven patients (ages 23-52) with neurologic impairment. The patients were evaluated with both
ice-water cystometry and formal video-urodynamic studies. Four biweekly courses of intravesical
capsaicin treatment were administered using increasing concentrations (100 microM, 500 microM, 1 mM, and 2 mM). Treatment effect was monitored using a bladder diary and urodynamic evaluation one month after
capsaicin treatment. Prior to treatment, six of the seven patients demonstrated a positive
ice-water test and DH. Two patients were not able to complete the study due to discomfort attributed to
capsaicin. Five of the seven patients completed the four courses of increasingly concentrated
capsaicin. Three patients noted symptomatic improvement while two did not. The mean urodynamic bladder capacity significantly increased from 124 +/- 39 ml pre-
capsaicin to 231 +/- 62 ml one month post-
capsaicin in the three patients with symptomatic improvement (p < 0.05). Urodynamic testing revealed that one of the six patients with a positive
ice-water test lost that response after intravesical
capsaicin. Intravesical
capsaicin is a novel and promising treatment for detrusor
hyperreflexia in neurologically impaired patients.