Angiotensin receptor blockers

Angiotensin receptor blockers (also called ARBs or angiotensin II inhibitors) are medicines that dilate (widen) blood vessels, and are used in the treatment of conditions such as high blood pressure (hypertension), heart failure, or kidney disease in people with diabetes.

ARBs work by blocking the action of a natural chemical called angiotensin II. Angiotensin II is a potent vasoconstrictor (causes blood vessels to constrict [narrow]). This narrowing can cause high blood pressure and poor blood flow through the kidneys. ARBs prevent angiotensin II from binding to angiotensin II receptors located in muscles surrounding blood vessels, thereby allowing those blood vessels to dilate, reducing blood pressure and improving symptoms of heart failure and progression of kidney disease due to diabetes. Angiotensin II also has effects on noradrenaline (noradrenaline contributes to vasoconstriction and increases heart rate), aldosterone secretion from the adrenal cortex, and sodium re-absorption and water retention by the kidneys.