OAB is usually treated by conservative measures or with oral medications eg. anticholinergics. Injection of onabotulinum toxin A (onaBoNT-A) into the bladder wall is licenced in the treatment of refractory IDO where oral medications fail. The injected toxin paralyses the bladder by blocking the ability of certain (motor) nerves to communicate with the bladder muscle. As these nerves are mainly concentrated in what is known as the "body" of the bladder this is traditionally where the injections are given.