How does candesartan function in the body?

Candesartan functions primarily as an angiotensin II receptor blocker (ARB). By selectively binding to angiotensin II receptors, particularly in vascular smooth muscle, it prevents the action of angiotensin II, a potent vasoconstrictor. This blockade leads to vasodilation, which results in lowering blood pressure by reducing peripheral resistance. Additionally, by inhibiting the effects of angiotensin II, candesartan also exerts effects on the adrenal glands which reduce the secretion of aldosterone, leading to decreased sodium and water retention.

This mechanism is central to its therapeutic use in conditions such as hypertension and heart failure. The other options describe mechanisms that are characteristic of other drug classes, such as ACE inhibitors or diuretics, rather than the specific action of candesartan.