Pharmacologic options for the overactive bladder

Abstract

Objectives. To review the current pharmacologic options for treatment of the overactive bladder and to describe potential therapies on the horizon. Methods. The literature on the clinical efficacy and safety of the currently available agents is described. Results. According to the guidelines issued by the Agency for Health Care Policy and Research (AHCPR), anticholinergic agents should be the first-line pharmacologic therapy for patients with detrusor instability. Oxybutynin is the anticholinergic of choice for this indication, whereas propantheline is the second-line therapy. Although calcium antagonists have been investigated, the one such drug introduced for the treatment of overactive bladder (terodiline) was withdrawn from the market because of a risk of cardiac arrhythmia. Studies of potassium channel openers have found either a lack of clinical efficacy or an unacceptable level of side effects. Alpha-adrenergic antagonists may be useful for decreasing bladder overactivity in patients who have autonomous bladders as the result of conditions such as spinal cord injury. Tricyclic antidepressants (particularly imipramine) may be effective in decreasing bladder contractility, although the AHCPR guidelines caution that these drugs should be reserved for use in carefully evaluated patients. Future developments in the treatment of detrusor overactivity are likely to occur in 3 categories: drugs that affect peripheral excitatory mechanisms, drugs that inhibit afferent mechanisms, and drugs that affect more central actions at either the ganglionic, spinal cord, or supraspinal level. Conclusions. Although pharmacologic management of the overactive bladder has progressed little in the past 10 years, the future may hold the promise of more effective therapies.