Repeat botulinum toxin-A injections for treatment of adult detrusor overactivity.

Intravesical injections of botulinum toxin-A have become established as an effective therapy in the management of neurogenic and idiopathic detrusor overactivity that is refractory to treatment with anticholinergic medication. The effects of the toxin are finite and repeated injections are required to sustain the beneficial therapeutic effects. The available data suggest a reproducible and sustained improvement in symptoms as well as urodynamic parameters following repeated injections of botulinum toxin-A. The reported incidence of adverse events is low and resistance to the toxin is uncommon. The timing of repeat injections within the published data is variable, reflecting differing practise among clinicians, but is typically 6-12 months. Larger scale studies are still required to clarify the usefulness of botulinum toxin-A as a long-term treatment in the management of detrusor overactivity.