What can be added to Flomax (tamsulosin) for Lower Urinary Tract Symptoms (LUTS) in a patient with hypertension?

Adding Medication to Tamsulosin for LUTS in a Patient with Hypertension

For patients with lower urinary tract symptoms (LUTS) already on tamsulosin who also have hypertension, adding a 5-alpha reductase inhibitor (5-ARI) like finasteride or dutasteride is the most appropriate option, especially if the patient has prostatic enlargement. 1

Medication Options to Add to Tamsulosin

5-Alpha Reductase Inhibitors (First Choice)

• 5-ARIs (finasteride or dutasteride) are appropriate additions to tamsulosin for patients with demonstrable prostatic enlargement 1
• These medications reduce prostate size by 18-28%, improve symptoms by 15-30%, and increase maximum flow rate by 1.5-2.0 ml/s 1
• 5-ARIs reduce the risk of acute urinary retention by 57-68% and need for surgery by 55-64% at 4 years 1
• Particularly effective for patients with larger prostates (>40 ml) 1

PDE5 Inhibitors (Alternative Option)

• Tadalafil 5mg daily is the only PDE5 inhibitor licensed for LUTS treatment 1
• Combination of PDE5 inhibitors with alpha-blockers can significantly improve IPSS score (-1.8), erectile function (+3.6), and maximum flow rate (+1.5 ml/s) compared to alpha-blocker monotherapy 1
• Important caution: Careful monitoring is required when combining with antihypertensive medications due to potential additive blood pressure-lowering effects 2

Muscarinic Receptor Antagonists (For Storage Symptoms)

• Consider for patients with predominant storage symptoms (urgency, frequency) 1
• Most effective in men with PSA levels <1.3 ng/ml 1
• Caution is needed regarding potential voiding difficulties and increased post-void residual volume 1

Special Considerations for Hypertensive Patients

Alpha-Blocker Considerations

• Tamsulosin has a lower probability of orthostatic hypotension compared to other alpha-blockers but higher probability of ejaculatory dysfunction 1
• Alpha-blockers used for LUTS should not be assumed to provide optimal management of hypertension; separate management of hypertension may be required 1

Medication Interactions

• When combining tamsulosin with PDE5 inhibitors like tadalafil, monitor for potential blood pressure effects 2
• Tadalafil should be used with caution in patients taking alpha-blockers or other antihypertensive medications due to potential for additive blood pressure lowering 2
• Tadalafil is contraindicated in patients using nitrates or guanylate cyclase stimulators 2

Treatment Algorithm

1. Assess prostate size (via DRE and/or PSA) 1

   • If prostate is enlarged (>40ml): Add a 5-ARI (finasteride or dutasteride)
   • If prostate is not enlarged: Consider other options based on symptom type

2. Evaluate predominant symptom type 1

   • For predominant voiding symptoms with enlarged prostate: Add 5-ARI
   • For mixed storage and voiding symptoms: Consider combination therapy
   • For predominant storage symptoms: Consider adding a muscarinic receptor antagonist

3. Consider erectile function 1

   • If erectile dysfunction is also present: Consider tadalafil 5mg daily (with careful blood pressure monitoring)

4. Monitor hypertension separately 1

   • Ensure hypertension is managed according to current guidelines
   • Follow the ISH 2020 recommendations for hypertension management 1

Potential Adverse Effects to Monitor

• 5-ARIs: Sexual dysfunction (reduced libido, erectile dysfunction, ejaculation disorders), effect on PSA (reduces by approximately 50%) 1
• PDE5 inhibitors: Flushing, gastroesophageal reflux, headache, dyspepsia, back pain, nasal congestion 1
• Muscarinic receptor antagonists: Dry mouth, constipation, dizziness, nasopharyngitis, and potential voiding difficulties 1

Follow-up Recommendations

• Assess treatment success of 5-ARIs after at least 3 months 1
• Monitor blood pressure control when combining medications, especially with PDE5 inhibitors 2
• Re-evaluate LUTS symptoms and potential side effects at follow-up visits 1