Drug therapy - Management of overactive bladder

Symptoms of overactive bladder are common, can be distressing, and are associated with serious adverse consequences such as injurious falls. The symptoms may be caused by myriad factors, including disorders of the lower urinary tract, neurologic conditions, behavioral factors such as caffeine intake, and a variety of commonly prescribed drugs. The pathophysiologic process in an individual patient is often multifactorial. Diagnostic evaluation includes a focused history taking, targeted physical examination, and urinalysis. Selected patients should have a post-void residual determination, and some should undergo cystoscopy (such as those with hematuria) or complex urodynamic testing (such as those with urinary retention or neurologic disorders). Patients with overactive bladder often benefit from supportive measures such as education, changes in fluid intake, and the use of bedside commodes or urinals, especially at night. Behavioral treatments such as pelvic-muscle exercises and bladder training are efficacious and can enhance the benefits of drug therapy. The mainstay of drug therapy is antimuscarinic agents. The two best-studied agents are oxybutynin and tolterodine; both have well-proven efficacy in short- and long-acting forms. The extended-release formulations and the oxybutynin skin patch are generally well tolerated, but all antimuscarinic drugs can have bothersome anticholinergic side effects. The effects of these agents on cognitive function are a particular concern in older adults. Men with symptoms of overactive bladder in association with benign prostatic hyperplasia may benefit from treatment with alpha-blockers. Promising future directions in drug therapy include the development of more specific antimuscarinic agents, new drug-delivery systems, and drugs that affect the sensory innervation of the lower urinary tract.