MISARTAN H is combination of Telmisartan 40 mg +?Hydrochlorothiazide 12.5 mg & is used to treat?high blood pressure?(hypertension). Lowering?high blood pressure?helps prevent strokes,?heart attacks, and?kidney?problems. Telmisartan belongs to a class of drugs called angiotensin receptor blockers (ARBs). It works by relaxing?blood?vessels so blood can flow more easily. Hydrochlorothiazide is a “water pill” (diuretic). It increases the amount of urine body is making, especially when patient first start the medication. It also helps to relax the blood vessels so that blood can flow more easily.These medications are used together when 1 drug alone is not controlling the blood pressure. The Doctor may direct patient to start taking the individual medications first, and then switch over to this combination product if this is the best dose combination for the patient.