New clinical evidence of silodosin, an α1A selective adrenoceptor antagonist, in the treatment for lower urinary tract symptoms.

Lower urinary tract symptoms associated with benign prostatic hyperplasia are highly prevalent in older men. Pharmacological treatment is the first-line treatment for lower urinary tract symptoms associated with benign prostatic hyperplasia. The first choice in the pharmacological treatment for lower urinary tract symptoms associated with benign prostatic hyperplasia is the α₁-adrenoceptor antagonists. Many α₁-adrenoceptor antagonists are available in the world. Silodosin is an α₁-adrenoceptor antagonist developed by Kissei Pharmaceutical, and has a specific selectivity for the α_1A-adrenoceptor subtype. By antagonizing α_1A-adrenoceptor in the prostate and urethra, silodosin causes smooth muscle relaxation in the lower urinary tract. As a result of the high affinity for the α_1A-adrenoceptor than for the α_1B-adrenoceptor, silodosin minimizes the propensity for blood pressure-related adverse effects caused by blockade of α_1B-adrenoceptor. The efficacy and safety of silodosin for treatment of lower urinary tract symptoms associated with benign prostatic hyperplasia was first reported by Japanese investigators in 2006. At present, silodosin is used in many countries. In the present review, we summarize the new clinical evidence for lower urinary tract symptoms associated with benign prostatic hyperplasia and introduce the data supporting the new clinical indications of silodosin. [ABSTRACT FROM AUTHOR]