[Intravesical treatment of overactive bladder syndrome].

Overactive bladder and urgency incontinence are common conditions generally treated with oral anticholinergic medication. Despite the development of new antimuscarinic substances, many patients are refractory to or cannot tolerate the oral therapy due to severe side effects. Intravesical instillation therapy can provide an alternative method to manage detrusor overactivity. Intravesical instillation of anticholinergics such as oxybutynin and trospium chloride can achieve cholinergic blockade without producing systemic side effects. Botulinum toxin type A injections into the detrusor have been shown to increase bladder capacity and to decrease detrusor overactivity for 6 or more months. Intravesical local anesthetics such as lidocaine and bupivacaine block the conduction of unmyelinated C fibers which results in an increase of functional bladder capacity. Intravesical capsaicin and resiniferatoxin also affect the afferent C fiber innervation of the bladder, leading to a decrease in detrusor overactivity and also an increased bladder capacity. The use of intravesical anticholinergics and of local anesthetic medications, both known for their short-term efficacy, is limited due to the necessity of daily intermittent catheterization. In conclusion, intravesical therapies can provide an alternative treatment for the management of overactive bladder.