Botulinum toxin-A for the treatment of overactive bladder: UK contributions

BACKGROUND: Botulinum toxin-A (BoNT/A) is now established second-line management for refractory overactive bladder (OAB) and recognised in many incontinence guidelines and pathways. For those with neurogenic detrusor overactivity secondary to spinal cord injury or multiple sclerosis, the toxin is currently licensed in certain parts of the world, including the UK. It is an effective treatment in those in whom antimuscarinics and conservative measures have failed who have symptoms of OAB and or detrusor overactivity (DO). METHODS: Treatment can be given in an outpatient setting and can be administered under local anaesthesia. Its efficacy lasts for between six and 12 months. RESULTS: It has an acceptable safety profile with the biggest risk being urinary tract infection and difficulty emptying the bladder, necessitating clean intermittent self-catheterisation (CISC). Medium-term follow-up suggests repeated injections are also safe and efficacious. CONCLUSIONS: The mechanism of action of the toxin is more complicated than originally thought, and it seems likely that it affects motor and sensory nerves of the bladder. In the last 10 years much of the progress of this treatment from early experimental trials to mainstream clinical use, and a better understanding of how it works in the bladder, are as a result of research conducted in the UK. This review summarises the significant and substantial evidence for BoNT/A to treat refractory OAB from UK centres.