What are the treatment options for overactive bladder (OAB)?

Treatment Options for Overactive Bladder (OAB)

All patients with OAB should begin with behavioral therapies as first-line treatment, followed by beta-3 adrenergic agonists (mirabegron) as the preferred pharmacologic option over antimuscarinics, and reserve minimally invasive procedures for those who fail both behavioral and pharmacologic interventions. 1, 2, 3

Initial Evaluation

Before initiating treatment, perform the following essential assessments:

• Obtain urinalysis to exclude microhematuria and infection, with urine culture if urinalysis suggests infection or hematuria 1, 2
• Measure post-void residual (PVR) in patients with emptying symptoms, history of urinary retention, enlarged prostate, neurologic disorders, prior incontinence/prostate surgery, or long-standing diabetes 1, 3
• Consider symptom questionnaires and voiding diaries to confirm diagnosis, assess symptom burden, and establish baseline for treatment response 1, 3

Critical caveat: Elevated PVR >250-300 mL warrants caution when prescribing antimuscarinics or beta-3 agonists due to urinary retention risk 2, 4

First-Line Treatment: Behavioral Therapies

Offer behavioral therapies to all patients regardless of symptom severity due to their excellent safety profile and absence of drug interactions 1, 2, 3:

• Timed voiding and urgency suppression techniques to re-establish normal voiding intervals 1, 3
• Fluid management with optimization of timing and volume, particularly reducing evening intake 2, 4
• Bladder irritant avoidance including caffeine and alcohol 1, 3
• Pelvic floor muscle training for improved urge control 2, 3
• Weight loss targeting 8% reduction in obese patients to reduce urgency incontinence episodes 3

Important consideration: Success depends heavily on patient acceptance and adherence, requiring adequate patient education 2, 3. Combination of behavioral and pharmacologic therapies provides better outcomes than either alone 3, 5.

Second-Line Treatment: Pharmacologic Therapies

Preferred Option: Beta-3 Adrenergic Agonists

Mirabegron is the preferred pharmacologic agent due to lower cognitive risk compared to antimuscarinics, particularly important in elderly patients 2, 3, 4:

• Starting dose: 25 mg orally once daily 6
• Maximum dose: 50 mg orally once daily after 4-8 weeks if needed 6
• Dose adjustments: For eGFR 15-29 mL/min/1.73 m² or Child-Pugh Class B hepatic impairment, maximum dose is 25 mg daily; avoid in eGFR <15 mL/min/1.73 m² or Child-Pugh Class C 6
• Drug interactions: Mirabegron is a moderate CYP2D6 inhibitor requiring monitoring with narrow therapeutic index substrates (thioridazine, flecainide, propafenone) and digoxin 6

Alternative Option: Antimuscarinic Medications

Antimuscarinics (darifenacin, fesoterodine, oxybutynin, solifenacin, tolterodine, trospium) are alternatives but require caution 2, 3:

• Contraindications/cautions: Narrow-angle glaucoma, impaired gastric emptying, history of urinary retention, cognitive impairment risk 2, 3
• Elderly patients: Avoid or use with extreme caution due to cognitive impairment risk; beta-3 agonists strongly preferred 2, 4

Treatment Optimization

• Allow 8-12 weeks to determine efficacy before changing therapies 3, 4
• If inadequate response: Consider dose modification, switching to different antimuscarinic, switching to beta-3 agonist, or combination therapy with antimuscarinic plus beta-3 agonist 2, 4
• Initiate behavioral and pharmacologic therapy simultaneously for optimal outcomes including improved frequency, voided volume, incontinence, and symptom distress 2

Third-Line Treatment: Minimally Invasive Therapies

For patients failing behavioral and pharmacologic interventions, refer to urology specialist for 2, 3:

• Intradetrusor onabotulinumtoxinA (100 units) - patients must be willing and able to perform clean intermittent self-catheterization if needed and return for frequent PVR evaluation 2, 3, 4
• Sacral neuromodulation (SNS) 2, 3
• Peripheral tibial nerve stimulation (PTNS) - requires frequent office visits 2, 3

Adjunctive Management Strategies

Incontinence Management Products

• Absorbent products (pads, liners, absorbent underwear), barrier creams, and external collection devices reduce adverse sequelae of incontinence but do not treat underlying condition 1, 2, 3

Comorbidity Optimization

Treat conditions that worsen OAB severity 1, 3:

• Benign prostatic hyperplasia (BPH)
• Constipation
• Diuretic timing optimization
• Obesity management
• Diabetes mellitus control
• Genitourinary syndrome of menopause
• Pelvic organ prolapse
• Tobacco cessation

Monitoring and Follow-Up

• Annual follow-up to assess treatment efficacy and detect symptom changes 3, 4
• Realistic expectations: Most patients experience significant symptom reduction rather than complete resolution 3
• Telemedicine option: Viable for initial evaluation but may require in-office visit with physical examination, PVR measurement, and urinalysis if no response to therapy 1