Beta-blockers, also known as -blockers, are a class of medications commonly prescribed to treat arrhythmias (Drugs such as Bisoprolol, metoprolol succinate), prevent secondary heart attacks, and sometimes manage hypertension. These drugs inhibit the activity of endogenous catecholaminesnamely epinephrine and norepinephrinewithin the sympathetic nervous system by targeting adrenergic beta-receptors. While some beta-blockers non-competitively block all beta-adrenergic receptors, others do so in a competitive manner. It is targeted at the beta receptor on the cell wall, selectively binds to the beta adrenergic receptor, antagonizes the excitatory effect of neurotransmitters and catecholamines on the beta receptor, and is mainly used in the treatment of hypertension, coronary heart disease, heart failure and other diseases, which can cause adverse reactions. Moreover, It may cause bradycardia, second degree type II and above atrioventricular block, bronchial asthma, and hypotension. Central nervous system adverse reactions, multiple dreams, hallucinations, insomnia, fatigue, vertigo and depression and other symptoms, especially high-fat soluble -blockers, easy to cross the blood-brain barrier to cause adverse reactions, such as propranolol. The commonly used -blockers in clinic include metoprolol, atenolol and ecolol. In the United States Food and Drug Administration (FDA) classification of drugs according to the degree of harm to pregnant women, most drugs are classified as class C or D.