What are the classifications of antihypertensive drugs?

Antihypertensive drugs are generally classified into several categories, including calcium channel blockers, angiotensin-converting enzyme (ACE) inhibitors, angiotensin II receptor antagonists, diuretics, and beta-blockers. A detailed analysis is as follows:

1. Calcium Channel Blockers: These drugs lower blood pressure by preventing calcium ions from entering vascular smooth muscle cells, leading to vasodilation and reduced peripheral vascular resistance. They are widely applicable, especially suitable for elderly patients with hypertension or those with stable angina, and have minimal effects on blood glucose and lipid levels.

2. Angiotensin-Converting Enzyme (ACE) Inhibitors: By inhibiting the activity of ACE, these drugs reduce the production of angiotensin II, resulting in vasodilation and decreased blood pressure. They are particularly beneficial for hypertensive patients with diabetic nephropathy or heart failure. However, some individuals may develop a dry cough after using these medications.

3. Angiotensin II Receptor Antagonists: These agents lower blood pressure by blocking the binding of angiotensin II to its receptors, thereby counteracting its vasoconstrictive effects. Their therapeutic effects are similar to those of ACE inhibitors, but they are associated with a lower incidence of dry cough, making them suitable for patients who cannot tolerate the cough caused by ACE inhibitors.

4. Diuretics: These drugs reduce blood pressure by promoting the excretion of water and electrolytes, thereby decreasing blood volume and cardiac load. They include thiazide diuretics and loop diuretics. Thiazide diuretics are more commonly used for mild to moderate hypertension. Long-term use requires regular monitoring of electrolyte levels.

5. Beta-Blockers: These drugs reduce blood pressure by suppressing sympathetic nervous system activity, slowing heart rate, reducing myocardial contractility, and decreasing cardiac output. They are particularly appropriate for hypertensive patients with coexisting tachyarrhythmias or coronary artery disease. Caution is advised in patients with asthma.

The selection of antihypertensive medications should be made by a physician based on blood pressure levels, comorbid conditions, and individual patient factors. Blood pressure should be monitored regularly during treatment, and patients must not discontinue or adjust their dosage without medical advice. If symptoms such as dizziness or fatigue occur, patients should promptly inform their doctor, and treatment regimens may need adjustment when necessary.