The difference between isosorbide mononitrate tablets and extended-release tablets is that regular tablets have a short duration of action and extended-release tablets have a long duration of action. Isosorbide mononitrate tablets belong to the ordinary tablets, after taking the drug to play a role in the time fast, can quickly relieve the patient’s symptoms, but the drug lasts for a relatively short period of time, you need to take the drug twice a day. Isosorbide mononitrate extended-release tablets have a long duration of action and can be taken once a day to ensure that the vasodilator effect is exerted throughout the day. Isosorbide mononitrate has the effect of dilating coronary arteries, mainly used in the treatment of coronary heart disease, the adverse effects of the drug are headache, head swelling, drowsiness, hypotension, etc. Allergy to the components of the drug, increased intracranial pressure, glaucoma, low blood pressure, etc., is prohibited in patients. Patients with coronary heart disease should choose the appropriate dosage form under the guidance of the physician for better relief of the patient’s symptoms.