What are the first-line medications for treating Overactive Bladder (OAB) in men?

First-Line Medications for Overactive Bladder (OAB) in Men

Anticholinergic medications (antimuscarinics) are the first-line pharmacological treatment for men with overactive bladder symptoms after behavioral therapies have been tried. 1

Treatment Algorithm

First-Line: Behavioral Therapies

• Behavioral therapies should be offered as initial treatment for all men with OAB symptoms 1
• These include bladder training, pelvic floor muscle exercises, fluid management, and delayed voiding techniques 1
• Behavioral therapies are as effective as antimuscarinic medications and have no side effects 1

Second-Line: Pharmacological Treatment

When behavioral therapies are insufficient:

Antimuscarinic Medications (First-line pharmacotherapy)

• Oral antimuscarinics that can be offered (in alphabetical order, no hierarchy implied) 1:
  • Darifenacin
  • Fesoterodine
  • Oxybutynin (immediate and extended release)
  • Solifenacin
  • Tolterodine (immediate and extended release)
  • Trospium

Beta-3 Adrenoceptor Agonists

• Mirabegron is an effective alternative to antimuscarinics 1
• May be preferred in men with concerns about cognitive side effects or dry mouth 1

Special Considerations for Men with OAB

Men with Coexisting BPH/LUTS

• Alpha blockers (e.g., tamsulosin) are first-line therapy for men with both BPH and OAB symptoms 1
• If storage symptoms persist after alpha blocker therapy, add an antimuscarinic or beta-3 agonist 1
• For men with prostate size >30cc, consider adding a 5-alpha reductase inhibitor (5-ARI) 1

Combination Therapy

• Antimuscarinic agents may be combined with alpha blockers for men with persistent OAB symptoms 1
• Combination therapy of solifenacin with tamsulosin has shown efficacy in clinical trials 1
• For patients refractory to monotherapy, combination of a beta-3 agonist (mirabegron) with an antimuscarinic may be considered 1

Efficacy and Safety Considerations

Efficacy

• Antimuscarinics reduce urgency, frequency, and urgency incontinence episodes 1
• Patients with more severe symptoms typically experience greater symptom reductions 1
• Complete symptom relief is uncommon, especially in patients with high baseline symptom levels 1

Safety Precautions

• Antimuscarinics should not be used in patients with narrow-angle glaucoma unless approved by an ophthalmologist 1
• Use with extreme caution in patients with:
  • Impaired gastric emptying
  • History of urinary retention
  • Cognitive impairment (especially in elderly patients) 1
• Measure post-void residual (PVR) in men at risk for urinary retention 1
• Use antimuscarinics cautiously in patients with PVR >250-300 mL 1

Common Side Effects

• Dry mouth (most common, usually mild to moderate) 1, 2
• Constipation
• Dry eyes
• Blurred vision
• Cognitive effects (especially in elderly patients) 1

Treatment Failure

• If patients fail to respond to behavioral and medical therapy, they should be referred to a specialist 1
• Third-line treatments include:
  • Sacral neuromodulation
  • Peripheral tibial nerve stimulation
  • OnabotulinumtoxinA injections 1

Evidence-Based Comparisons

• Behavioral therapy alone is superior to drug therapy alone for reducing voiding frequency (8.8 vs 10.3 voids/day) 3
• Combined behavioral and drug therapy is superior to drug therapy alone but not to behavioral therapy alone 3
• Tolterodine has similar efficacy to oxybutynin but with fewer side effects, particularly dry mouth 2
• In men already on alpha-blockers, adding behavioral therapy or antimuscarinic therapy shows equivalent improvement in symptoms 4