Adrenaline, a hormone secreted by the human adrenal cortex, is secreted when people experience shock or excitement to provide more energy to the body, that is, it can accelerate the heartbeat, it can make the blood pressure rise, and it can make the blood vessels dilate. It is generally used clinically for resuscitation of patients in cardiac arrest and anaphylaxis, as well as for other allergic diseases such as bronchial asthma and urticaria. The main effect is to make the heart contraction force rise, which makes the heart and liver blood vessels dilate, and the skin and mucous membrane blood vessels contract. It is used to stimulate the heart in case of cardiac arrest and to dilate the airways in case of asthma. For the skin, mucous membrane, and visceral vessels, it is a contraction effect; for the coronary arteries and skeletal muscle vessels, it is a dilation effect, which can act directly on the coronary arteries to cause vasodilation, and finally to improve the blood supply to the heart. Clinically, it is often pushed quietly and used to treat shock more often.