Angiotensin receptor blockers block the final common pathway and provide a means of complete blockade of the system.
One of two subtypes of AII receptors, the AT1 receptor produces vasoconstriction and induces muscle cell proliferation when activated; the AT2 receptor produces antiproliferative effects upon activation. Currently available ARBs selectively block the AT1 receptor, producing vasodilatation and inhibiting muscle cell proliferation.
However, these agents do not produce increases in bradykinin, prostaglandins, and nitric oxide in the heart, blood vessels, and other tissues. They should be considered as alternatives to ACE inhibitors in ACE-intolerant patients especially patients with chronic dry irritating cough and angiedema. Another potential use is to counteract ACE escape, the attenuation of the benefits of ACE inhibition that may occur with time.
Various agents available are losartan, valsartan, irbesartan, candesartan, telmisartan and eprosartan.