Intravesical Botox for overactive bladder; how to minimize complications and manage failures

Intravesical Botox has become a widespread treatment for patients with refractory overactive bladder. Further to its acknowledged efficacy, both physicians and patients must be fully aware of possible complications, such as urinary tract infections, incomplete bladder emptying or even urinary retention and possible need for intermittent selfcatheterizations, fatigue, muscle weakness, transient hematuria and autonomic dysreflexia. Careful patient selection, particularly in terms of comorbidities, caution with technical aspects of the procedure such as the use of fine specifically designed injection needles, treatment of baseline UTIs or bacteriuria, avoidance of bladder overfilling could be the main measures, in addition to rigorous patient follow-up, to minimize the risk of post-Botox UTIs, hematuria, autonomic dysreflexia, and retention. Management of Botox failures is currently an unchartered area, starting with the definition of failure per se. Nevertheless, dose increase, particularly in neurogenic patients, increase of treatment frequency, switch to abobotulinumtoxinA, prolongation of injection intervals with add-on oral therapy, use of percutaneous tibial nerve stimulation or sacral neuromodulation and alleviation of risk factors for failure such as UTIs may be part of the management algorithm for Botox failures. As there is little evidence base to support such proposals and as the use of intravesical Botox is increasingly becoming a part of common urological practice, further research into the field of Botox failures and complications is needed so that both physicians and patients are granted with more solid, viable options.

Keywords: Botox; bladder; botulinum toxin; detrusor; idiopathic; neurogenic; onabotulinumtoxinA; overactive.