What is the recommended treatment for an adult with a spastic (overactive) bladder without neurogenic etiology, urinary infection, or severe obstructive disease?

Treatment of Spastic (Overactive) Bladder

For adults with non-neurogenic overactive bladder, begin with behavioral therapies as first-line treatment, then add oral medications (antimuscarinics or beta-3 agonists) if symptoms persist, and reserve third-line interventions like botulinum toxin injections or neuromodulation for refractory cases. 1

First-Line Treatment: Behavioral Therapies

All patients should receive behavioral interventions before or alongside pharmacologic treatment 1, 2:

• Bladder training and delayed voiding to increase bladder capacity and reduce urgency 1, 2
• Pelvic floor muscle training for urge suppression techniques 1, 2
• Fluid management with attention to total daily intake and timing 1, 3
• Caffeine and alcohol avoidance as bladder irritants 1, 2
• Weight loss in overweight patients, as obesity worsens OAB 1, 2
• Treatment of constipation which can exacerbate bladder symptoms 1

Common Pitfall: Many clinicians skip directly to medications without adequately implementing behavioral therapies, which are effective and have no adverse effects 1.

Second-Line Treatment: Oral Medications

If behavioral therapies are insufficient after 4-8 weeks, add pharmacologic treatment 1:

Antimuscarinic Medications

• Solifenacin is FDA-approved for OAB with symptoms of urge urinary incontinence, urgency, and urinary frequency 4
• Other options include oxybutynin, tolterodine, trospium, darifenacin, and propiverine 5
• Caution: Use antimuscarinics carefully in patients with post-void residual (PVR) of 250-300 mL, as they may worsen retention 2, 6
• Common adverse effects include dry mouth, constipation, and blurred vision 1, 5

Beta-3 Adrenergic Agonists

• Mirabegron 25-50 mg once daily is effective for reducing incontinence episodes, micturition frequency, and increasing voided volume 7
• Mirabegron 50 mg showed statistically significant improvements within 4 weeks of treatment 7
• Advantage: Beta-3 agonists do not significantly increase risk of urinary retention compared to antimuscarinics 2

Critical Consideration: Before starting antimuscarinics, measure PVR in patients with obstructive symptoms, history of retention, prostatic enlargement, neurologic disorders, or long-standing diabetes to avoid worsening retention 1, 6.

Third-Line Treatment: Minimally Invasive Therapies

For patients refractory to behavioral and oral therapies, consider referral to a specialist 1, 3:

Intradetrusor OnabotulinumtoxinA Injection

• Offer to carefully selected patients who have failed first- and second-line treatments 1
• Essential requirement: Patient must be willing and able to perform intermittent self-catheterization if needed, as urinary retention requiring catheterization occurs in approximately 5% of patients 1, 8
• Requires repeat injections as effects diminish over time 1
• Adverse events include UTIs and elevated PVR 1

Sacral Neuromodulation (SNS)

• Offer as third-line treatment in carefully selected patients compliant with long-term protocols 1
• Benefits appear to outweigh risks in appropriate patients with severe OAB affecting quality of life 1

Percutaneous Tibial Nerve Stimulation (PTNS)

• May be offered as third-line treatment in carefully selected patients 1
• Typical protocol: 30 minutes of stimulation once weekly for 12 weeks 1
• Limitation: Requires ongoing treatment with frequent office visits to maintain improvements 1
• Adverse events are relatively uncommon and mild 1

Fourth-Line Treatment: Invasive Procedures (Rarely Used)

Augmentation Cystoplasty or Urinary Diversion

• Consider only in extremely rare cases of severe, refractory, complicated OAB 1
• Substantial risks include need for long-term intermittent self-catheterization and risk of malignancy 1
• Little evidence exists for non-neurogenic OAB patients 1

Indwelling Catheters

• Not recommended except as absolute last resort due to high risk of catheter-associated UTIs, urethral erosion, and urolithiasis 1, 6
• Management with absorbent products is always preferred 1
• May be considered only when urinary incontinence has resulted in progressive decubitus ulcers 1

Special Population: OAB with Benign Prostatic Hyperplasia

For men with both OAB and BPH 2:

• Offer antimuscarinic or beta-3 agonist monotherapy, OR
• Offer combination therapy with an alpha blocker plus antimuscarinic or beta-3 agonist
• Both antimuscarinics and beta-3 agonists do not significantly increase retention risk in this population 2

Follow-Up Strategy

Regular follow-up is essential to assess treatment compliance, efficacy, side effects, and discuss alternative treatments 1:

• Encourage patients to persist with treatment for 4-8 weeks to identify responders 1
• Reassess if treatment goals are not met 6
• Use validated symptom questionnaires and voiding diaries to monitor response 1, 2

Critical Pitfall: Inadequate follow-up to assess treatment efficacy and manage adverse events is common and leads to treatment failure 9.