Lower urinary tract symptoms and sexual dysfunction: a common approach.

Area of Science:

• Urology
• Pharmacology

Background:

• Alpha(1)-adrenergic blockers (alpha(1)-blockers) are primary treatments for lower urinary tract symptoms (LUTS) associated with benign prostatic hyperplasia.
• Phosphodiesterase type-5 (PDE-5) inhibitors are first-line therapies for erectile dysfunction (ED).
• The high prevalence of co-occurring LUTS and ED suggests increased co-prescription of these drug classes.

Purpose of the Study:

• To review the interaction and potential benefits of co-administering alpha(1)-blockers and PDE-5 inhibitors for LUTS and ED.
• To explore the rationale and evidence for combination therapy in managing these related conditions.

Main Methods:

• Review of interaction studies between selective alpha(1)-blockers (alfuzosin, tamsulosin) and tadalafil.
• Examination of in vitro data on the relaxant effects of alfuzosin and tadalafil on detrusor muscle, prostate tissue, and corpus cavernosum.
• Analysis of a pilot study on the tolerability and efficacy of daily alfuzosin and sildenafil combination therapy.

Main Results:

• Tadalafil (a PDE-5 inhibitor) has minimal impact on blood pressure when combined with alfuzosin or tamsulosin.
• Alpha(1)-blockers generally show placebo-like incidence of ED, with some potential benefits, except tamsulosin causing anejaculation.
• PDE-5 inhibitors demonstrate positive effects on LUTS, likely through distinct mechanisms from alpha(1)-blockers.
• In vitro studies indicate additive relaxant effects of alfuzosin and tadalafil on relevant human tissues.
• A pilot study suggests that daily low-dose alfuzosin and sildenafil is well-tolerated and potentially more effective than monotherapy for LUTS and ED.

Conclusions:

• Combination therapy with alpha(1)-blockers and PDE-5 inhibitors is a rational approach for treating concurrent LUTS and ED.
• Evidence suggests potential additive benefits and good tolerability for specific combinations.
• Further research is necessary to confirm the clinical value of this combination therapy.