Is finasteride (Propecia) or tamsulosin (Flomax) more effective for treating Benign Prostatic Hyperplasia (BPH)?

From the Guidelines

For patients with benign prostatic hyperplasia (BPH), finasteride is generally recommended over tamsulosin for those with larger prostates (>30cc) or a PSA >1.5ng/mL, as it has been shown to reduce the risk of acute urinary retention and the need for BPH-related surgery, as stated in the 2021 AUA guideline 1.

Key Considerations

• Finasteride works by shrinking the prostate gland itself, which takes 3-6 months to show full effects, whereas tamsulosin works quickly to relax prostate and bladder neck muscles, improving urine flow and reducing symptoms.
• The 2021 AUA guideline recommends combination therapy with an alpha blocker (such as tamsulosin) and a 5-ARI (such as finasteride) for patients with LUTS associated with demonstrable prostatic enlargement, as judged by a prostate volume of >30cc on imaging, a PSA >1.5ng/mL, or palpable prostate enlargement on DRE 1.
• The choice between finasteride and tamsulosin should be based on the patient's specific symptoms, prostate size, and personal considerations, with finasteride being more beneficial for men with larger prostates.

Side Effects and Monitoring

• Tamsulosin may cause dizziness, retrograde ejaculation, and orthostatic hypotension, while finasteride can cause sexual side effects like decreased libido and erectile dysfunction, and requires PSA monitoring.
• The combination of an alpha-adrenergic receptor blocker and a 5 alpha-reductase inhibitor has been found to be more effective in relieving and preventing the progression of symptoms than alpha-blocker monotherapy, especially in patients with larger prostates and higher PSA values 1.

Clinical Decision Making

• The decision to use finasteride, tamsulosin, or combination therapy should be made on a case-by-case basis, taking into account the patient's individual risk factors, symptom severity, and personal preferences.
• The 2021 AUA guideline provides a strong recommendation for the use of combination therapy in patients with LUTS associated with demonstrable prostatic enlargement, with a Grade A evidence level 1.

From the Research

Comparison of Finasteride and Tamsulosin for BPH

• Tamsulosin is a subtype-selective alpha(1A)- and alpha(1D)-adrenoceptor antagonist that relaxes smooth muscle in the prostate and bladder neck, enhancing bladder emptying 2.
• Studies have shown that tamsulosin improves obstructive voiding symptoms by at least 25% in 65-80% of patients with symptomatic benign prostatic hyperplasia (BPH) 3.
• Tamsulosin also improves peak urinary flow rate by 1.4-3.6 mL/sec and reduces post-void residual urine volume 3.
• The usual dosage of tamsulosin is 0.4 or 0.8 mg orally once a day, with a rapid onset of action and no need for initial dosage titration 3.
• Finasteride, on the other hand, is a 5-alpha-reductase inhibitor that reduces prostate size and improves symptoms, but its effects may take longer to manifest compared to tamsulosin 4.
• A study comparing alpha 1-blockers (including tamsulosin) with finasteride found that alpha 1-blockers are more effective in relieving symptoms and improving urinary flow, especially in patients with mild to moderate BPH 4.

Efficacy and Safety of Tamsulosin

• Tamsulosin has been shown to be effective and well-tolerated in the treatment of lower urinary tract symptoms (LUTS) associated with BPH, with a low potential for hypotensive effects or interference with concomitant antihypertensive therapy 2, 5.
• The most common adverse effects of tamsulosin are headache, asthenia, dizziness, and rhinitis-like complaints, with retrograde or delayed ejaculation occurring in 4.5-14.0% of patients 3.
• Intermittent tamsulosin therapy (0.4 mg/every other day) has been shown to be well-tolerated and may improve ejaculatory function in patients with LUTS/BPH who experience abnormal ejaculation with daily tamsulosin therapy 6.

Combination Therapy with Finasteride

• A study found that combination therapy with tamsulosin and finasteride improved symptoms and quality of life in patients with BPH, especially in those with moderate to severe symptoms 5.
• However, the study also noted that tamsulosin monotherapy was effective in improving symptoms and urinary flow, and that the addition of finasteride may not be necessary for all patients 5.