ACEI class antihypertensive drugs, also known as angiotensin converting enzyme inhibitors, have the following characteristics: 1. The onset of antihypertensive is slow, it is 3-4 weeks to reach the maximum antihypertensive effect, if used in combination with diuretics, it can work quickly to enhance its effect. 2. ACEI can also protect the heart in addition to lowering blood pressure, it can improve myocardial remodeling, and is suitable for patients with heart failure combined with hypertension. 3. ACEI has the effect of improving insulin resistance and reducing urinary protein, which is suitable for patients with hypertension combined with diabetes, diabetic nephropathy and microprotein amount. 4. During the use of ACEI, we should pay attention to the side effect of dry cough, and monitor the level of blood potassium and blood creatinine.