Silodosin

Silodosin is a selective antagonist of alpha(α)-1 adrenergic receptors that binds to the α subtype with the highest affinity. α1-adrenergic receptors regulate smooth muscle tone in the bladder neck, prostate, and prostatic urethra: the α subtype accounts for approximately 75% of α1-adrenoceptors in the prostate.

Silodosin was first approved by the FDA in October 2008 and it is also approved in Europe and Canada. Silodosin is available as oral capsules with common trade names Rapaflo and Urorec. It is indicated for the symptomatic treatment of benign prostatic hyperplasia in adults. Most commonly affecting males over the age of 40 years, benign prostatic hyperplasia is the non-malignant enlargement of the prostate gland, associated with lower urinary tract symptoms that have a negative impact on the quality of life of patients. Silodosin works by binding to α-adrenoceptors with high affinity and relaxing the lower urinary tract, thereby improving urinary symptoms and alleviating bladder outlet obstruction.