What medications can be used to treat stress and urge incontinence?

Medication Management for Stress and Urge Incontinence

For urge incontinence, antimuscarinic medications are recommended after failed behavioral therapy, while no systemic medications are recommended for stress incontinence as first-line treatment. 1

Treatment Algorithm by Incontinence Type

Stress Urinary Incontinence

1. First-line: Non-pharmacological approaches

   • Pelvic floor muscle training (PFMT) 1, 2
   • Weight loss and exercise for obese patients 1, 2

2. Pharmacological options (limited effectiveness)

   • Vaginal estrogen formulations may improve continence and stress UI 1
   • Duloxetine (not FDA-approved in US for this indication)
     • Can improve quality of life scores 3
     • Reduces incontinence episodes by approximately 50% 4
     • High discontinuation rate (24%) due to side effects, primarily nausea 4
     • Risk-benefit ratio is questionable 5

3. Important note: The American College of Physicians strongly recommends against systemic pharmacologic therapy for stress UI due to low-quality evidence of effectiveness 1

Urge Incontinence

1. First-line: Non-pharmacological approaches

   • Bladder training 1, 2
   • Weight loss and exercise for obese patients 1, 2

2. Second-line: Pharmacological options (if bladder training unsuccessful) 1

   • Antimuscarinic medications:

     • Oxybutynin: Highest risk for discontinuation due to adverse effects 1
     • Tolterodine: Better side effect profile than oxybutynin 2, 6
     • Solifenacin: Lowest risk for discontinuation due to adverse effects 1, 2
     • Darifenacin: Risk for discontinuation similar to placebo 1, 2
     • Fesoterodine: Higher rates of adverse effects than tolterodine 2
     • Trospium: Lower incidence of constipation compared to other antimuscarinics 2

   • Beta-3 adrenergic agonists:

     • Mirabegron: Preferred in older adults due to better cognitive safety profile 2

Mixed Incontinence

• Combination of PFMT with bladder training 1
• If behavioral therapy fails, consider pharmacological treatment based on predominant symptoms 1

Medication Selection Considerations

Efficacy

• All antimuscarinic medications are similarly effective for urge incontinence 1
• Medication choice should be based primarily on side effect profile, tolerability, and cost 1

Side Effect Management

1. Common antimuscarinic side effects:

   • Dry mouth (most common with oxybutynin at 71.4%) 2
   • Constipation (15.1% with oxybutynin) 2
   • Blurred vision (9.6% with oxybutynin) 2
   • Dizziness (16.6% with oxybutynin) 2
   • Somnolence (14% with oxybutynin) 2

2. Contraindications:

   • Avoid antimuscarinics in patients with:
     • Narrow-angle glaucoma 2, 6
     • Significant gastric emptying problems 2
     • Urinary retention 6

3. Duloxetine considerations:

   • High discontinuation rate (approximately 1 in 8 patients) 3
   • Nausea is the most common side effect 7, 3
   • Risk of drug interactions via CYP1A2 and CYP2D6 pathways 5
   • Rare but serious adverse effects including suicide attempts and hepatic disorders 5

Clinical Pearls and Pitfalls

• Patient adherence: Adherence to pharmacological treatments for UI is generally poor 1
• Medication discontinuation: Adverse effects are a major reason for treatment discontinuation 1
• Monitoring: Balance the risk of pharmacologic adverse effects against the severity of symptoms 1
• Underreporting: At least half of women with UI do not report the issue to their physician 1
• Cognitive effects: Consider cognitive safety profile when selecting medications, especially in older adults 2
• Transdermal options: Consider transdermal formulations if oral side effects are intolerable 2

By following this algorithm and considering individual patient factors, clinicians can optimize the management of both stress and urge incontinence while minimizing adverse effects.