Botulinum toxin A (BTX-A) inhibits acetylcholine exocytosis from parasympathetic postganglionic nerves to the M2 and M3 receptors of the detrusor, inhibiting detrusor contraction. BTX-A (100– 200u) is injected into the detrusor muscle during cystoscopy. It decreases overactivity, urgency, and storage pressures 1)
Efficacy lasts 3–12 months and repeat injections are required. Maximum Botox dose is 360u per 90 day from all sources. Side effects include urinary tract infection and urinary retention. In patient not already managed with catheterization, must be aware of the risk of urinary retention and need for temporary catheterization in 2–20% of patients 2).
This is usually self-limited to weeks or months as the BTX-A wears off 3).
This is usually self-limited to weeks or months as the BTX-A wears off.