Persistent therapeutic effect of repeated injections of onabotulinum toxin a in refractory bladder pain syndrome/interstitial cystitis.

Purpose: We evaluate the efficacy and safety of repeated intratrigonal injections of onabotulinum toxin A in patients with bladder pain syndrome/interstitial cystitis.Materials and Methods: This is a single center, long-term, prospective study in which 16 women with bladder pain syndrome/interstitial cystitis refractory to standard treatment received 4 consecutive intratrigonal injections of onabotulinum toxin A. Onabotulinum toxin A (100 U) was injected under cystoscopic control in 10 trigonal sites, each receiving 10 U in 1 ml saline. General anesthesia was used in all treatments. Re-treatment was allowed 3 months after injection. Outcome measures included pain visual analog scale (0–10), O'Leary-Sant score, a 3-day voiding chart and a quality of life questionnaire at the first month and every 3 months after each injection. Voiding dysfunction and urinary tract infections were assessed at 2 weeks and every 3 months afterward. Treatment duration was determined when patients requested another injection.Re...