Timosartan and hydrochlorothiazide are two different types of antihypertensive drugs, the combination of which will increase the antihypertensive effect and may offset the adverse effects of low potassium. Timosartan is an antihypertensive drug, which mainly acts on angiotensin II receptors and has the effect of dilating peripheral blood vessels, and it can lower blood pressure and protect potassium at the same time. Hydrochlorothiazide is also an antihypertensive drug, belongs to the diuretic, in the lowering of blood pressure at the same time can discharge potassium, the two drugs at the same time will enhance the effect of lowering blood pressure, may avoid the adverse effects of hypokalemia. Timosartan belongs to the western prescription drugs, the adverse reactions of the drug are headache, dizziness, fatigue, abdominal pain, flu-like symptoms, dyspepsia, etc. It is forbidden to patients who are allergic to the drug components, severe liver and kidney function impairment, late pregnancy and lactating women, and biliary tract obstruction. Hydrochlorothiazide belongs to the western prescription drugs, the adverse reactions of the drug are thirst, nausea, vomiting, fatigue, dry mouth, hypokalemia, etc. It is forbidden for patients who are allergic to the drug components. Timosartan and hydrochlorothiazide combined with good antihypertensive effect, clinically under the guidance of the physician to use the drug, while paying attention to the adverse effects of the drug.