1. It has a certain excitatory effect on the heart, can constrict blood vessels, and produce an increase in blood pressure; 2. It has the effect of dilating the trachea and bronchi; 3. It has an antithrombotic effect; 4. It can transiently enhance the tension of vascular smooth muscle; it has anti-allergic effects. Clinically, it is used for shock, heart failure, treatment of bronchial asthma, hypotension during surgery and anesthesia, collapse and shock, as well as postural hypotension.