At present, the antihypertensive drugs with fewer side effects are mainly the first-line antihypertensive drugs. The first-line antihypertensive drugs include diuretics, beta-blockers, angiotensin-converting enzyme inhibitors, angiotensin II receptor antagonists and calcium channel blockers. These drugs are widely used in clinical practice, and their effects are also very significant, with relatively few side effects, which is why they are widely promoted in clinical practice. The representative drugs of diuretics are furosemide and hydrochlorothiazide. The representative drugs of beta-blockers are metoprolol and bisoprolol, etc. The representative drugs of angiotensin-converting enzyme inhibitors are perindopril, fosinopril, etc. The representative drugs of angiotensin II receptor antagonists are colesartan, valsartan, etc. The representative drugs of calcium channel blockers include felodipine, amlodipine, etc.