According to the different mechanisms of action of hypertensive drugs, there are five major classes of drugs: calcium antagonists, angiotensin-converting enzyme inhibitors, angiotensin receptor antagonists, diuretics, and beta-blockers. 1, diuretics: mainly through the lina urination, reduce the volume load and play a role in lowering blood pressure. Such as tachyphylaxis, dihydrocoumaric acid. 2, β-blockers: mainly through the inhibition of excessive activation of sympathetic nerve activity, inhibition of myocardial contractility, slowing down the heart rate to play a hypotensive effect. Such as metoprolol, bisoprolol. 3, angiotensin-converting enzyme inhibitors: the mechanism of action is to inhibit angiotensin-converting enzyme, block the generation of renin angiotensin II, inhibit the degradation of kinase and play a role in lowering blood pressure. Such as benazepril, lenopril, etc. 4, angiotensin II receptor antagonist: the mechanism of action is to block the angiotensin III receptor and exert antihypertensive effect. arb is especially suitable for patients with left ventricular hypertrophy, heart failure, diabetic nephropathy, coronary artery disease, metabolic syndrome, microalbuminuria or proteinuria, and patients who cannot tolerate ACEI, and can prevent atrial fibrillation. Such as valsartan, temisartan, etc. 5, calcium channel blockers: mainly by blocking calcium channels on vascular smooth muscle cells to play the role of vasodilation to lower blood pressure. Including dihydropyridine CCB and non-dihydropyridine CCB, such as amlodipine, nifedipine, etc.. These drugs have different mechanisms of action and can be used in the initial and maintenance treatment of hypertension, but each has its own characteristics and indications.