Betalucil is metoprolol tartrate, an adrenergic beta-blocker. Metoprolol tartrate is not recommended for coronary artery spasm. Beta adrenergic receptors are divided into β1, β2 and β3. β1 receptors are mainly distributed in the heart, and can increase myocardial contractility, autoregulation and conduction function during excitation. β2 receptors are mainly distributed in bronchial smooth muscle, vascular smooth muscle and myocardium, and mediate the effects of relaxation and vasodilatation of bronchial smooth muscle, and β3 receptors are mainly distributed in the white and brown adipose tissues, and regulate energy metabolism. Although metoprolol tartrate mainly blocks the β1 receptor, but also has a certain effect on the β2 receptor, when coronary artery spasm, if the β2 receptor is blocked, it is equivalent to blocking the relaxation of coronary vascular smooth muscle, which will further exacerbate the spasm of the coronary artery, therefore, the use of metoprolol tartrate is not recommended for coronary artery spasm. Clinical use of the drug should follow the doctor’s instructions, do not take without authorization, in order to avoid serious consequences.