Metoprolol tartrate extended-release tablets have the effect of lowering the heart rate and blood pressure, and can be taken correctly following the doctor’s instructions for the treatment of hypertension, arrhythmia and other diseases. Metoprolol tartrate is a β-blocker, can play a selective blocking effect on β1-receptors, can reduce pacemaker cell autoregulation, prolong atrial conduction time, used in the treatment of tachyarrhythmia; it can also reduce peripheral vascular resistance, significantly reduce the blood pressure in the lying down position, the upright position and the exercise, used in the treatment of hypertension. In addition to this, acute myocardial infarction, hyperthyroidism, and hypertrophic cardiomyopathy may also be taken as prescribed. As this drug may cause side effects such as headache, palpitations, nausea, vomiting, etc., it must be taken properly under medical supervision. The drug should not be used by people with cardiogenic shock, significant bradycardia, or sick sinus node syndrome.