The first time to take isosorbide mononitrate should follow the doctor’s instructions to pay attention to the way of taking the drug and the dose, if there is an adverse reaction after taking the drug should be adjusted under the guidance of the doctor in a timely manner. 1. Dosage: Isosorbide mononitrate oral drug commonly used dosage forms are tablets, capsules, extended-release agents and sprays, it should be noted that tablets, capsules and extended-release agents can not be chewed to take medication, should be swallowed as a whole, and sprays are generally sprayed with sublingual spray. 2. Dosage: Isosorbide mononitrate should follow the doctor’s instructions to choose the appropriate dosage form and the amount of medication, the first time to take the dosage should follow the doctor’s instructions, not overdose. If dizziness, palpitations, nausea, vomiting, sweating and other adverse reactions occur after the first dose, should be reduced under the advice of a doctor, serious treatment. It should be noted that if the drug is to be discontinued, the dosage should be gradually reduced to avoid rebound phenomenon. If you suffer from glaucoma, hypertrophic obstructive cardiomyopathy, acute myocardial infarction, shock, etc., you can not use the drug. It is recommended to use the drug under the supervision of a physician.