What is the recommended dosage of solifenacin for treating overactive bladder?

Solifenacin Dosing for Overactive Bladder

Start with solifenacin 5 mg once daily, and increase to 10 mg once daily only if the 5 mg dose is well tolerated and additional symptom control is needed. 1

Standard Dosing Regimen

• The FDA-approved starting dose is 5 mg taken orally once daily with water, swallowed whole, with or without food 1
• The dose may be escalated to 10 mg once daily if the 5 mg dose is well tolerated 1
• Clinical trials demonstrate that over half of incontinent patients achieve continence with the 5 mg dose alone after 12 weeks of treatment 2

Dose Restrictions in Special Populations

You must cap the dose at 5 mg once daily in three specific situations:

• Severe renal impairment (creatinine clearance < 30 mL/min/1.73 m²) - do not exceed 5 mg daily 1
• Moderate hepatic impairment (Child-Pugh B) - do not exceed 5 mg daily; solifenacin is contraindicated in severe hepatic impairment (Child-Pugh C) 1
• Concurrent use of strong CYP3A4 inhibitors (such as ketoconazole) - do not exceed 5 mg daily 1

Combination Therapy Considerations

• For postmenopausal women with inadequate response to monotherapy, the combination of solifenacin 5 mg plus mirabegron 50 mg demonstrates superior efficacy compared to either agent alone 3, 4
• For men with both storage and voiding lower urinary tract symptoms, solifenacin may be combined with tamsulosin 5
• The American Urological Association recognizes the solifenacin 5 mg plus mirabegron 50 mg combination as the most effective medication regimen for overactive bladder in postmenopausal women 3

Clinical Efficacy Timeline

• Symptom improvements are observed as early as week 2 of treatment and are maintained over 12-week and 1-year periods 6
• The 5 mg dose provides statistically significant reductions in incontinence episodes, micturition frequency, urgency episodes, and increases in volume voided compared to placebo 2, 7

Common Pitfalls to Avoid

• Do not start at 10 mg - always initiate at 5 mg, as this dose provides substantial efficacy with lower anticholinergic side effects (dry mouth incidence comparable to placebo) 8
• Do not use in patients with urinary retention, gastric retention, or uncontrolled narrow-angle glaucoma - these are absolute contraindications 1
• Exercise caution in elderly patients - monitor for cognitive effects and anticholinergic burden, though solifenacin efficacy is not compromised by patient age 6
• Monitor for angioedema - can occur after first dose or after multiple doses; discontinue immediately if tongue, hypopharynx, or larynx involvement occurs 1

Monitoring Parameters

• Assess for adverse effects including dry mouth, constipation, and blurred vision at follow-up visits 3
• Monitor for urinary retention, especially in patients with bladder outlet obstruction 3
• Evaluate treatment efficacy using symptom questionnaires and bladder diaries 3