NCIt definition : A synthetic imidazole derivative and angiotensin II receptor antagonist with antihypertensive
activity. Olmesartan selectively binds to the angiotensin type 1 (AT1) receptor subtype
in vascular smooth muscle and adrenal gland, thereby competing with angiotensin II
for binding to the AT1 receptor. This prevents angiotensin II-induced vasoconstriction
and interferes with angiotensin II-mediated aldosterone secretion, thereby decreasing
aldosterone production and preventing aldosterone-stimulated sodium retention and
potassium excretion.;