There are five major classes of antihypertensive drugs commonly used in clinical practice, of which beta-blockers can lower heart rate and also lower blood pressure. However, it should be noted that there are some contraindications to beta blockers, for example, they are not recommended for patients with a slow heart rate of less than 60 beats, especially less than 55 beats. Others, such as patients with bronchial asthma or chronic obstructive pulmonary disease exacerbations, are not recommended, nor are they recommended for patients with atrioventricular block of degree II or higher. Several other classes of antihypertensive drugs include calcium antagonists, such as nifedipine and amlodipine. There are also angiotensin-converting enzyme inhibitors, such as Yashida. Angiotensin II receptor antagonists, such as cloxacin and valsartan. There is also a class of diuretics, clinically used hydrochlorothiazide, spironolactone and other antihypertensive effect is also relatively good, in the clinic is also very commonly used.