What are the management options for overactive bladder?

Management Options for Overactive Bladder

Beta-3 adrenoceptor agonists (such as mirabegron) are recommended as the preferred first-line pharmacological treatment for overactive bladder (OAB), followed by antimuscarinic medications if needed, due to their efficacy and lower risk of cognitive side effects. 1

First-Line Management: Conservative Approaches

Behavioral Modifications

• Lifestyle interventions:
  • Weight loss (even 8% reduction can decrease incontinence episodes by up to 47%) 1
  • Fluid management (reduce intake by approximately 25%) 1
  • Elimination of bladder irritants (caffeine, alcohol, spicy foods) 1
  • Establishing timed voiding schedules based on bladder diary 1

Bladder Training

• Start with short voiding intervals (1-2 hours) and gradually increase as control improves 1
• Pelvic floor muscle training exercises 1
• These behavioral therapies are as effective as antimuscarinic medications with no risk of adverse effects 1

Second-Line Management: Pharmacological Options

First-Choice Medication

• Beta-3 adrenoceptor agonists (mirabegron):
  • Preferred first-line pharmacological treatment 1
  • Lower risk of cognitive side effects compared to antimuscarinics
  • Dosage adjustments needed for renal impairment (based on eGFR) and hepatic impairment (based on Child-Pugh score) 1

Alternative Medications

• Antimuscarinic medications:
  • Options include oxybutynin, tolterodine, trospium, solifenacin, and darifenacin 1
  • Use with caution in elderly patients, those with narrow-angle glaucoma, impaired gastric emptying, or history of urinary retention 1
  • For elderly patients (>65 years), start with lower doses (e.g., oxybutynin 2.5mg twice daily) 1

Combination Therapy

• Combination of antimuscarinic and beta-3 adrenoceptor agonist for patients refractory to monotherapy
• Most evidence supports solifenacin (5 mg) with mirabegron (25 or 50 mg) 1

Third-Line Management: Advanced Interventions

For Refractory OAB

• Intradetrusor onabotulinumtoxinA (100 U):

  • FDA-approved for OAB when antimuscarinics don't work well enough 2
  • Monitor for potential side effects including urinary retention and UTI 2

• Neuromodulation options:

  • Sacral neuromodulation (SNS)
  • Peripheral tibial nerve stimulation (PTNS) 1

Treatment Algorithm

1. Initial approach: Behavioral modifications + bladder training (2-4 weeks)
2. If insufficient improvement: Add pharmacotherapy
   • First choice: Beta-3 adrenoceptor agonist (mirabegron)
   • If contraindicated or ineffective: Antimuscarinic medication
   • Consider combination therapy if monotherapy fails
3. If still inadequate response after 3 months: Refer to specialist for consideration of:
   • Intradetrusor onabotulinumtoxinA
   • Sacral neuromodulation
   • Peripheral tibial nerve stimulation

Management of Common Adverse Effects

• Dry mouth: Switch to extended-release formulations or transdermal options 1
• Constipation: Increase fluid and fiber intake, consider stool softeners 1
• Urinary retention: Check post-void residual; consider dose reduction or discontinuation if >200 mL 1

Follow-up and Monitoring

• Assess treatment success or failure at appropriate intervals:
  • 2-4 weeks for antimuscarinic therapy
  • 3 months for beta-3 agonists 3
• Annual follow-up for successful treatment to detect any changes in symptoms 3
• If treatment fails and patient is not satisfied, reassess and consider alternative or advanced therapies 3

Important Cautions

• Antimuscarinic medications should be used with extreme caution in elderly patients due to increased risk of cognitive effects 1
• OnabotulinumtoxinA can cause serious side effects including problems with breathing, swallowing, and spread of toxin effects 2
• Patients should be educated that OAB symptoms are rarely cured but can be significantly improved with appropriate management 4