What is the treatment for overactive bladder?

Treatment of Overactive Bladder

For overactive bladder treatment, behavioral therapies should be offered as first-line treatment to all patients before initiating pharmacologic therapy, followed by beta-3 adrenergic receptor agonists such as mirabegron as the preferred first-line pharmacologic option due to their lower risk of cardiovascular and cognitive side effects. 1

First-Line Treatment: Behavioral Therapies

Lifestyle Modifications

• Weight loss: Even modest weight loss (8%) can reduce incontinence episodes by up to 47% in obese patients 1
• Fluid management: Reduce fluid intake by approximately 25% and eliminate or significantly reduce caffeine intake 1, 2
• Bladder training: Establish a timed voiding schedule based on the patient's bladder diary, starting with short intervals (1-2 hours) and gradually increasing as control improves 1
• Pelvic floor muscle training: Patients should learn proper pelvic floor muscle contraction techniques and practice regularly 1

Second-Line Treatment: Pharmacologic Therapy

First-Line Pharmacologic Option

• Beta-3 adrenergic receptor agonists (Mirabegron):
  • Starting dose: 25mg daily with food 1, 3
  • Shows effectiveness within 8 weeks at 25mg; 50mg shows effectiveness within 4 weeks 1
  • May increase to 50mg after 4-8 weeks if needed 3
  • Monitor for adverse effects: hypertension, headache, and nasopharyngitis 1
  • Preferred in elderly patients due to lower risk of cognitive side effects 1

Alternative Pharmacologic Options

• Antimuscarinic medications:
  • Options include oxybutynin, solifenacin, darifenacin, fesoterodine, tolterodine, or trospium 1, 4
  • Oxybutynin starting dose: 5 mg 2-3 times daily 1
  • Tolterodine is indicated for OAB with symptoms of urge incontinence, urgency, and frequency 4
  • Use with caution in elderly patients due to risk of cognitive impairment 1
  • Common side effects: dry mouth, constipation, and blurred vision 5

Combination Therapy

• Consider combination therapy with an antimuscarinic plus beta-3 adrenergic receptor agonist for patients who fail to achieve adequate symptom relief with monotherapy 1
• Combination therapy shows superior efficacy in reducing incontinence episodes and micturitions, though adverse events may be slightly increased 1

Special Considerations

Renal Impairment (for Mirabegron)

• eGFR 30-89 mL/min/1.73 m²: Start 25mg, max 50mg
• eGFR 15-29 mL/min/1.73 m²: Start 25mg, max 25mg
• eGFR <15 mL/min/1.73 m²: Not recommended 3

Hepatic Impairment (for Mirabegron)

• Child-Pugh Class A (Mild): Start 25mg, max 50mg
• Child-Pugh Class B (Moderate): Start 25mg, max 25mg
• Child-Pugh Class C (Severe): Not recommended 3

Men with Concomitant BPH

• Alpha blockers are typically initial therapy for men with LUTS/BPH 1
• Consider combination of alpha-blocker and antimuscarinic 1
• For prostate size >30cc, consider adding 5-alpha reductase inhibitors (5ARIs) 1
• If erectile dysfunction is present, phosphodiesterase-5 inhibitors may be considered as initial therapy 1

Third-Line Treatment: Advanced Therapies

If pharmacotherapy fails to provide adequate symptom relief, consider:

1. Intradetrusor onabotulinumtoxinA injections 1
2. Neuromodulation therapies:
   • Peripheral tibial nerve stimulation (PTNS)
   • Sacral neuromodulation (SNS) 1
3. Intermittent catheterization if emptying is incomplete 1

Common Pitfalls and Caveats

• Antimuscarinic medications should be used with extreme caution in elderly patients due to risk of cognitive impairment 1
• Fluid restriction should be balanced to avoid dehydration while managing symptoms 2
• Comorbidity management is crucial - address conditions that may worsen OAB symptoms, such as BPH, constipation, and diabetes 1
• Most cases of OAB are not cured, but rather the symptoms are reduced with an associated improvement in quality of life 5
• OAB is not a normal consequence of aging, despite increased prevalence with age 6

By following this stepwise approach, starting with behavioral therapies and progressing to pharmacologic options when necessary, most patients with OAB can achieve significant symptom improvement and enhanced quality of life.