Intravesical botulinum toxin A injections in the treatment of painful bladder syndrome/interstitial cystitis: a systematic review

Intravesical botulinum toxin A (BTX-A) is emerging as a potential new treatment for refractory interstitial cystitis (IC). However, there has been conflicting evidence on this treatment's effectiveness. The aim of our systematic review was to assess the effectiveness and adverse effects of intravesical BTX-A in IC. Randomised controlled trials (RCTs) and prospective studies of relevance were identified, assessed for inclusion and then analysed by two independent reviewers. Ten (three RCTs and seven prospective cohort) studies with a total of 260 participants were included. Eight studies reported improvement in symptoms. Urodynamic parameters were variable. Meta-analysis was not performed due to heterogeneity in reporting of outcomes. Some adverse events, e.g. dysuria and voiding difficulty, were noted (19 out of 260 were required to self-catheterise at anytime postoperatively). The evidence from the studies thus far suggests a trend towards short-term benefit with intravesical BTX-A injections in refractory IC, but further robust evidence should be awaited.