Betalucil is the trade name, generic drug name Metoprolol, the drug long-term oral discontinuation of the drug should be gradually reduced, can not suddenly stop the drug. The main effect of metoprolol is to be able to inhibit the body’s beta receptors, can slow down the contractility of the heart muscle, indirectly reduce cardiac oxygen consumption, is the basic medication for patients with coronary artery disease, and at the same time can be used to control the ventricular rate, the treatment of tachyarrhythmia, but also used in the treatment of high blood pressure. Patients taking metoprolol for a long time can not suddenly stop taking the drug, otherwise it may lead to the aggravation of the original symptoms, or even induce angina pectoris, myocardial infarction, etc. Therefore, patients taking metoprolol for a long time, such as the condition of the patient to reduce the dosage of metoprolol, need to reduce the dosage gradually, and it is recommended that the dosage should be adjusted once a week to reach the minimum maintenance amount, if the condition allows, you can discontinue the drug. Adverse effects of metoprolol include dizziness, fatigue, low blood pressure, bradycardia, dyspnea, gastric upset, etc. It is contraindicated for patients with allergy to drug components, second or third degree atrioventricular block, severe bradycardia, cardiogenic shock, bronchial asthma, and so on. Metoprolol dose adjustment should follow the doctor’s instructions, avoid reducing the dose too quickly, to prevent symptoms rebound.