What medications are used to treat overactive bladder?

Medications for Overactive Bladder

First-line treatment for overactive bladder (OAB) should be behavioral therapies, with pharmacologic management as second-line therapy using either antimuscarinic agents or β3-adrenoceptor agonists based on patient characteristics and risk factors. 1

Treatment Algorithm

First-Line: Behavioral Therapies

• Bladder training
• Pelvic floor muscle training
• Fluid management (25% reduction in fluid intake)
• Weight loss (if obese)
• Avoidance of bladder irritants (caffeine, alcohol)

Second-Line: Pharmacologic Management

Antimuscarinic Medications

• Solifenacin (5-10 mg daily)
• Tolterodine (2-4 mg daily extended-release)
• Fesoterodine (4-8 mg daily)
• Oxybutynin (5-10 mg daily extended-release or transdermal)
• Trospium (20 mg twice daily or 60 mg daily extended-release)
• Darifenacin (7.5-15 mg daily)

β3-adrenoceptor Agonists

• Mirabegron (25-50 mg daily)
• Vibegron (75 mg daily)

Combination Therapy

For patients refractory to monotherapy, consider combination of:

• Antimuscarinic + β3-adrenoceptor agonist (e.g., solifenacin 5 mg + mirabegron 50 mg)

Medication Selection Considerations

Prefer β3-adrenoceptor Agonists When:

• Patient is elderly
• Cognitive concerns exist
• Patient has history of constipation, dry mouth, or narrow-angle glaucoma

Prefer Antimuscarinic Agents When:

• Lower cost is important
• More extensive clinical experience is desired

Contraindications for Antimuscarinic Agents:

• Narrow-angle glaucoma (unless approved by ophthalmologist)
• Impaired gastric emptying
• History of urinary retention

Efficacy Considerations

Antimuscarinic agents have shown similar efficacy in reducing OAB symptoms, with some differences in side effect profiles 1, 2:

• Solifenacin has better efficacy than tolterodine with lower risk of dry mouth 3
• Extended-release tolterodine (4 mg) shows improved clinical effectiveness compared to extended-release oxybutynin (10 mg) with better tolerability 4
• Transdermal oxybutynin may be preferred if dry mouth is a concern 1

Side Effects Management

Common Antimuscarinic Side Effects:

• Dry mouth (most common)
• Constipation
• Blurred vision
• Cognitive effects (especially in elderly)

Common β3-adrenoceptor Agonist Side Effects:

• Hypertension
• Headache
• Nasopharyngitis

Special Populations

Men with BPH and OAB:

Consider combination therapy with an alpha-blocker plus an antimuscarinic agent 1, 3:

• Tamsulosin + solifenacin
• Doxazosin + tolterodine

Elderly Patients:

• Prefer β3-adrenoceptor agonists due to lower risk of cognitive effects 3
• If using antimuscarinics, consider trospium (quaternary amine with lower CNS penetration) 2

Monitoring Recommendations

• Assess treatment response by tracking frequency, urgency episodes, and incontinence
• Monitor for signs of urinary retention, especially in at-risk patients
• Obtain post-void residual measurement if symptoms worsen

Important Caveats

• Complete symptom relief is unlikely; most patients experience significant reduction in symptoms
• Patients with more severe baseline symptoms typically experience greater symptom reduction
• Treatment discontinuation due to side effects is common with antimuscarinic agents
• Combination therapy may increase efficacy but also increases side effect risk

If patients fail to respond adequately to behavioral and pharmacologic management, third-line options include intradetrusor onabotulinumtoxinA injections, peripheral tibial nerve stimulation, or sacral neuromodulation 1.