Olmesartan (Benicar®,Olmetec®) belongs to the class of medicines called angiotensin II receptor antagonists to treat high blood pressure. It is marketed worldwide by Daiichi Sankyo, Ltd. and in the United States by Daiichi Sankyo, Inc. and Forest Laboratories. Olmesartan works by blocking the binding of angiotension II to the AT 1 receptors in vascular muscle; it is therefore independent of angiotension II synthesis pathways, unlike ACE inhibitors. By blocking binding rather than synthesis of angiotension II, olmesartan inhibits the negative regulatory feedback on renin secretion. As a result of this blockage, olmesartan restricts vasoconstriction and the secretion of aldosterone. This lowers blood pressure by producing vasodilation, and decreasing peripheral resistance.