The indications for metoprolol tartrate extended-release tablets are for the treatment of hypertension, angina pectoris, myocardial infarction, hypertrophic cardiomyopathy, aortic coarctation, arrhythmia, hyperthyroidism, and cardiac neurosis. The drug belongs to the β1-blocking drug without partial agonistic activity, which reduces blood pressure by lowering cardiac output, inhibiting renin release and reducing sympathetic excitation of the vasoconstrictor center; it also reduces the increase in heart rate, systolic blood pressure and degree of myocardial contraction induced by catecholamines or exercise, and reduces myocardial oxygen consumption; and it can play the role of membrane stabilization, affecting myocardial action potential. Therefore, it is clinically used in the treatment of hypertension, angina pectoris, myocardial infarction, hypertrophic cardiomyopathy, aortic coarctation, arrhythmia, hyperthyroidism, cardiac neurosis and other diseases. Adverse reactions such as headache, dizziness, diarrhea, and fatigue have been observed after administration. Significant bradycardia, cardiogenic shock, severe or acute heart failure, II or III degree AV block, sick sinus node syndrome, and severe peripheral vascular disease are contraindicated. It should be used with caution in hypotension, cardiac or hepatic insufficiency; it should be closely observed in the treatment of patients with type 1 diabetes mellitus; it should be used with caution in pregnant and lactating women. If medication is needed, it should be used under the guidance of a specialist.