Can Vesicare and Flomax Be Taken Together?
Yes, Vesicare (solifenacin) and Flomax (tamsulosin) can be safely taken together, and this combination is specifically recommended for men with both storage and voiding lower urinary tract symptoms.
Evidence for Combined Use
The combination of solifenacin and tamsulosin has been extensively studied and is supported by major urological guidelines:
The European Association of Urology specifically recommends combination therapy with solifenacin and tamsulosin for men who have both benign prostatic hyperplasia (BPH) and storage symptoms of overactive bladder 1.
A fixed-dose combination tablet containing tamsulosin 0.4 mg and solifenacin 6 mg has been developed and studied, demonstrating both efficacy and safety 1, 2, 3.
Clinical Trial Evidence
The NEPTUNE trial, a large randomized controlled study of 1,334 men, demonstrated that:
The combination of solifenacin 6 mg plus tamsulosin 0.4 mg significantly improved both storage symptoms (urgency, frequency) and voiding symptoms compared to tamsulosin alone 4.
Total International Prostate Symptom Score (IPSS) improved by -7.0 points with combination therapy versus -6.2 with tamsulosin alone and -5.4 with placebo 4.
Quality of life measures improved significantly with combination therapy 4.
The combination was well tolerated with low incidences of acute urinary retention, the primary safety concern when combining these medications 4.
Who Benefits Most
The combination is particularly effective for:
Men with moderate to severe storage symptoms (urgency episodes ≥2 per day, micturitions ≥8 per day) plus voiding symptoms 4, 5.
Patients who have persistent storage symptoms despite alpha-blocker monotherapy 5.
Safety Profile
The NEPTUNE/NEPTUNE II studies demonstrated that urinary retention during treatment with solifenacin plus tamsulosin combinations for up to 1 year was low 1.
Common adverse events reflect the known effects of each component:
- Dry mouth (from solifenacin)
- Dizziness or orthostatic hypotension (from tamsulosin)
- Constipation (from solifenacin) 4, 6
Important Caveats
Solifenacin should not be used as monotherapy for BPH but only in combination with alpha-blockers like tamsulosin 1.
Use extreme caution in patients with impaired gastric emptying, history of urinary retention, or narrow-angle glaucoma 7.
The optimal dose is solifenacin 6 mg (not 9 mg) combined with tamsulosin 0.4 mg, as higher solifenacin doses showed no additional benefit 4, 6.
Practical Implementation
Start tamsulosin first if the patient has predominantly voiding symptoms 1.
Add solifenacin if storage symptoms persist or are bothersome 1.
A single fixed-dose combination tablet is available and may improve compliance 3, 6.
Monitor for urinary retention, particularly in the first few weeks, though incidence is low 1, 4.