Pharmacologic Management of Overactive Bladder and Urge Incontinence: A Review of New and Old Treatment Options

Within the wall of the bladder is a rich network of parasympathetic efferent fibers and postganglionic cell bodies. There is little sympathetic innervation of the bladder; therefore the primary neurotransmitter involved in voluntary micturition is acetylcholine. In the male urinary tract, the neck of the bladder does contain sympathetic innervation to prevent retrograde ejaculation, thus responds to adrenergic stimulation as well [3,4]. The afferent nerve fibers in the bladder are activated by increased intra-vesical pressure, bladder stretch, as well as existing urine flow. These fibers initiate signals to urinate when the bladder is full, as well as to continue urinating until the bladder is empty [3].