The difference between isosorbide nitrate tablets and isosorbide mononitrate tablets lies in the structure, and there is a significant difference in the half-life of the drugs. Isosorbide nitrate and isosorbide mononitrate both belong to the nitrate class of drugs, with the effect of dilating coronary arteries, both can be used for the treatment of angina pectoris caused by coronary heart disease. There is a certain difference in the structure of the two, resulting in a certain difference in the pharmacokinetics of the drug, isosorbide mononitrate half-life of 4-6 hours, the effect of a relatively long time, can be taken twice a day. Isosorbide nitrate belongs to the short-acting drugs, need to be taken orally three times a day, the duration of the drug is relatively short. Adverse reactions of isosorbide nitrate tablets include headache, head swelling, tachycardia, dizziness, hypotension, etc. This drug is contraindicated in patients with acute circulatory failure, severe hypotension, acute myocardial infarction with low filling pressures, hypertrophic obstructive cardiomyopathy. Adverse reactions to isosorbide mononitrate tablets include vasodilatory headache, markedly low blood pressure, bradycardia, worsening angina and syncope, etc. This drug is contraindicated in patients with acute circulatory failure, severe hypotension, acute myocardial infarction with low filling pressure, hypertrophic obstructive cardiomyopathy, constrictive pericarditis or pericardial tamponade, and glaucoma. Nitrate drugs should be used under the guidance of a doctor, and pay attention to the adverse effects of the drug in the process of using the drug.