Candesartan HCTZ is a prescription medicine that combines candesartan cilexetil, an angiotensin II receptor blocker (ARB), with hydrochlorothiazide, a thiazide diuretic. Together, they help treat high blood pressure by relaxing blood vessels and increasing the amount of fluid removed by the kidneys. By controlling high blood pressure, this combination reduces the risk of strokes, heart attacks, and kidney damage. This dual action makes it effective for patients who haven’t achieved blood pressure control with candesartan or other medicines alone.