AZILSARTAN MEDOXOMIL, A PRODRUG, IS HYDROLYZED TO AZILSARTAN IN THE GASTROINTESTINAL TRACT DURING ABSORPTION. AZILSARTAN IS A SELECTIVE AT1 SUBTYPE ANGIOTENSIN II RECEPTOR ANTAGONIST. ANGIOTENSIN II IS FORMED FROM ANGIOTENSIN I IN A REACTION CATALYZED BY ANGIOTENSIN-CONVERTING ENZYME (ACE, KININASE II). ANGIOTENSIN II IS THE PRINCIPAL PRESSOR AGENT OF THE RENIN-ANGIOTENSIN SYSTEM, WITH EFFECTS THAT INCLUDE VASOCONSTRICTION, STIMULATION OF SYNTHESIS AND RELEASE OF ALDOSTERONE, CARDIAC STIMULATION, AND RENAL REABSORPTION OF SODIUM. AZILSARTAN BLOCKS THE VASOCONSTRICTOR AND ALDOSTERONE-SECRETING EFFECTS OF ANGIOTENSIN II BY SELECTIVELY BLOCKING THE BINDING OF ANGIOTENSIN II TO THE AT 1 RECEPTOR IN MANY TISSUES, SUCH AS VASCULAR SMOOTH MUSCLE AND THE ADRENAL GLAND. ITS ACTION IS THEREFORE INDEPENDENT OF THE PATHWAYS FOR ANGIOTENSIN II SYNTHESIS.