Tribenzor contains a combination of amlodipine, hydrochlorothiazide, and olmesartan. Amlodipine is a calcium channel blocker that relaxes (widens) blood vessels and improves blood flow. Hydrochlorothiazide is a thiazide diuretic (water pill) that helps prevent your body from absorbing too much salt, which can cause fluid retention. Olmesartan is an angiotensin II receptor antagonist that keeps blood vessels from narrowing, which lowers blood pressure and improves blood flow. Tribenzor is used to treat high blood pressure (hypertension).