Finasteride Alpha blockers

Finasteride can be administered alone or in combination with the alpha-blocker doxazosin. 

Geriatric Considerations - Summary Alpha-adrenergic blockers are modestly effective alone, and in combination with 5-alpha reductase inhibitors (e,g, finasteride) in the treatment of urinary obstructive symptoms related to benign prostatic hyperplasia. Alfuzosin is a "uroselective" alpha-blockerwhich appears to cause less orthostatic hypotension than nonselective alpha-blockers such as terazosin, prazosin, and doxazosin. 

Sadeghi-Nejad H, Sherman N, Lue J. Comparison of finasteride and alpha-blockers as independent risk factors for erectile dysfunction. Int J Clin Pract 2003 57 484-7. 

Pharmacology In vitro studies have shown inhibition of 5a-reductase and antagonistic effects at androgen receptors. Clinical trials of saw palmetto in benign prostatic hyperplasia (BPH) have shown improvement in urologic function and in urinary flow. When compared with finasteride in BPH, saw palmetto did not lower prostate-specific antigen or dihydrotestosterone levels. However, sexual dysfunction was less with saw palmetto than with finasteride. Clinical improvement of BPH with saw palmetto appears to be less than that with alpha-blockers. 

A recent study by Bach, Schmitt, and Ebeling compared three prescriptive medications with a standardized saw palmetto extract. The drugs worked by two different mechanisms. Finasteride is a synthetic 5-alpha-reductase inhibitor, and the other two drugs, terazosin and alfuzosin, are alpha-1 blockers. In all important parameters, the saw palmetto was a comparable treatment with far fewer side effects. It decreased residual urine volume, reduced irritation, and increased urinary flow 80 percent of patients rated their improved quality of life as good to very good. 

---