The two differ in their indications. Enalapril maleate is indicated for patients with hypertension combined with decreased renal function and diabetes mellitus as well as for its ability to improve ventricular remodeling. Nifedipine is indicated for simple systolic hypertension, angina pectoris and coronary artery disease. 1. Enalapril maleate belongs to angiotensin-converting enzyme inhibitors, through the inhibition of angiotensin-converting enzyme, reduces the production of angiotensin, so that its vasoconstrictive ability to reduce blood pressure. Adverse effects of enalapril maleate include dizziness, lightheadedness, drowsiness, dry mouth, nausea, palpitations and irritating dry cough. It is contraindicated in hyperkalemia, pregnant women, and in those with severe bilateral renal artery stenosis. Individual patients, especially in the application of diuretics or reduced blood volume, may cause excessive drop in blood pressure. 2. Nifedipine is a 1,4 dihydropyridine calcium antagonist, which, by dilating the coronary arteries, especially the large vessels, can reduce the tension of coronary artery smooth muscle, prevent vasospasm, increase the blood flow of narrowed blood vessels, and improve the oxygen supply. Long-term use of nifedipine can prevent the occurrence of new coronary atherosclerotic disease. Adverse reactions to nifedipine include headache, edema, vasodilation, and constipation. Nifedipine is contraindicated in hypersensitivity to nifedipine or any of its components, cardiogenic shock and in women within 20 weeks of pregnancy and lactation. Both of these drugs have adverse effects, and it is recommended to regulate the use of medication under the supervision of a physician.