Managing the Flow: Treatment Options for Overactive Bladder
By Gina D. Moore, PharmD, MBA
Non-neurogenic overactive bladder (OAB) is characterized by the presence of urinary urgency, which is usually accompanied by urinary frequency and nocturia, with or without urinary incontinence, in the absence of infection or other pathology (Haylen, 2010).Patients typically report bothersome urinary frequency during the day, as well as sleep interruptions at night because of the need to void. Urinary incontinence is related to the urgent need to urinate, which differs from stress incontinence, or urinary leakage relating to physical activity or coughing/sneezing.
The American Urological Association and the Society of Urodynamics, Female Pelvic Medicine and Urogenital Reconstruction recently released updated guidelines for the diagnosis and overall management of adult patients with OAB (Gormley, 2012). Patients should be interviewed to determine that their voiding patterns are not caused by excessive fluid intake or related to medications, and are indeed bothersome enough to the individual to warrant treatment. Patients should be counseled that therapies may improve symptoms, but are unlikely to provide complete relief. Before pharmacologic interventions are attempted, patients should be offered behavioral treatments.
Behavioral interventions include:
- Bladder training
- Fluid management
- Exercises that strengthen pelvic floor muscles
Comparative effectiveness trials suggest that behavioral treatments are either equivalent to, or superior to, medications in regard to improving frequency and quality of life (Gormley, 2012).
Since the guidelines were published in December 2012, two new agents have been approved by the FDA for treatment of OAB. The first agent is mirabegron (Myrbetriq®), which works by relaxing the smooth muscle during the storage phase of the bladder fill-void cycle. Its main side effect is elevated blood pressure. The starting dose of mirabegron is 25 mg once daily, which may be increased to 50 mg once daily if needed (Myrbetriq, 2013).
The second FDA approval was for onabotulinumtoxinA, or Botox®, which is injected directly in the bladder muscle every 12 weeks or longer, depending on the patient’s symptoms. Botox is relatively costly, and is indicated for patients who do not respond to, or cannot use, antimuscarinic agents (FDA, 2013).
Other pharmacological options include oral antimuscarinics agents such as darifenacin, fesoterodine, oxybutynin, solifenacin, tolterodine or trospium.
Because these agents block muscarinic receptors, dry mouth, constipation, dry eyes, blurred vision, dyspepsia, and impaired cognition may occur. Similar efficacy has been demonstrated with all agents, but they do differ in terms of the occurrence of side effects. The incidence of constipation and dry mouth is typically higher in patients treated with oxybutynin versus the newer agents. If an extended release (ER) formulation is available, it is generally preferred due to fewer patient reports of dry mouth. Extended release formulations are specifically available for oxybutynin, tolterodine and trospium.
Patients with narrow angle glaucoma, a history of delayed gastric emptying, or a history of urinary retention should generally not use antimuscarinic agents. Patients taking other medications with anti-cholinergic activity are also not good candidates for this class of drugs. The 2012 Beers List also specifically advises against use of oral antimuscarinic agents to treat urinary incontinence in the setting of chronic constipation in older adults (AGS, 2012).
- Geriatrics Society [AGS]. (2012). Updated Beers Criteria for Potentially Inappropriate Medication Use in Older Adults. Journal of the American Geriatric Society. Retrieved from http://www.americangeriatrics.org/files/documents/beers/2012BeersCriteria_JAGS.pdf
- Federal Drug Administration [FDA]. (2013). FDA News Release: FDA approves Botox to treat overactive bladder. Retrieved from http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm336101.htm
- Gormley, et al. (2012). Diagnosis and Treatment of Overactive Bladder (Non-Neurogenic) in Adults: AUA/SUFU Guideline. Journal of Urology; 188:2455-2463.
- Haylen, B., de Ridder, D., Freeman, R., et al. (2010). An International Urogynecological Association (IUGA)/International Continence Soceity (ICS) joint report on the terminology for female pelvic floor dysfunction. Neurourol Urodyn, 29:4. Myrbetriq Product Information. (2013). Retrieved from http://www.us.astellas.com/docs/Myrbetriq_WPI.pdf
© 2013. AMN Healthcare, Inc. All Rights Reserved.
Biography Gina Moore is Director of Clinical Affairs and Assistant Professor in the Department of Clinical Pharmacy at the University of Colorado Skaggs School of Pharmacy and Pharmaceutical Science. She is responsible for numerous projects and entrepreneurial partnerships with the university. Moore is also a speaker at RxSchool.com where she presents live webinar courses and contributes to the site’s CE curriculum.