Also Known As: Tamsulosin, Flomax, Flomaxtra, Contiflo XL, Urimax
Tamsulosin (rINN) is an Î±1a-selective alpha blocker used in the symptomatic treatment of benign prostatic hyperplasia (BPH). Tamsulosin was developed by Yamanouchi Pharmaceuticals (now part of Astellas Pharma) and was first marketed under the trade name Flomax. It is now marketed by various companies under licence, including Boehringer-Ingelheim and CSL.
Tamsulosin hydrochloride extended-release capsules are marketed under the trade names Flomax, Flomaxtra, Contiflo XL and Urimax, although generic, non-modified-release capsules are still approved and marketed in many countries (such as Canada). In Colombia, it is marketed under Uripur from Laboratorios BussiÃ© and under Harnal D in Japan and Indonesia. In Egypt, Italy and Iceland, it is marketed under the trade name Omnic by Astellas Pharma Europe.
The U.S. patent for Flomax expired in October 2009. The U.S. Food and Drug Administration (FDA) approved generic Flomax in March 2010.
Tamsulosin is a selective α1 receptor antagonist that has preferential selectivity for the α1A receptor in the prostate versus the α1B receptor in the blood vessels.
When alpha 1 receptors in the bladder neck and the prostate are blocked, this causes a relaxation in smooth muscle and therefore less resistance to urinary flow. Due to this the pain associated with BPH can be reduced.