Ephedrine can directly agonize epinephrine receptors and can indirectly agonize epinephrine receptors by promoting the release of depot epinephrine from epinephrine nerve endings, and has agonistic effects on both alpha and beta receptors. It is mainly used to prevent bronchial asthma attacks and mild asthma attacks, but is not effective for acute severe asthma attacks. It can be used for hypotension caused by subarachnoid or epidural anesthesia and chronic hypotension, and can also treat nasal congestion caused by congestion and swelling of the nasal mucosa from various etiologies. Long-term heavy use can have adverse effects and may cause tremors, anxiety, insomnia, headache, palpitations, feverish feeling, sweating, etc. Take it at night with sedative-hypnotic drugs, such as phenobarbital, to prevent insomnia.