中药麻黄及其制剂(麻杏止咳片,止咳喘颗粒,咳喘丸,五海咳喘片,气管炎号片,止咳糖浆等)在临床上用于止咳、平喘症。据近代研究表明,麻黄中的主要有效成分为麻黄碱。由于麻黄碱系拟肾上腺素药,其化学结构类似于肾上腺素,故可松弛支气管平滑肌,从而达到止咳、平喘的作用。临床上有时医师将其与氨茶碱并用,企图获得相加或协同作用。麻黄碱与氨茶碱均是平喘药,松弛支气管平滑肌的作用机制相似,但作用环节亦不同,前者增加 Herbal ephedra and its preparations (Mingxing Zhike Tablets, Zhikechuan Granules, Kechuan Pills, Wuhai Kechuan Tablets, Tracheitis Tablets, Cough Syrup, etc.) are used clinically for cough and asthma. According to recent studies, the main active ingredient in ephedra is ephedrine. Due to its chemical structure similar to that of epinephrine, ephedrine-type adrenergic drugs can relax bronchial smooth muscles and thus achieve cough and asthma relief. At times, clinicians use it with aminophylline in an attempt to obtain an additive or synergistic effect. Ephedrine and aminophylline are antiasthmatic drugs. The mechanism of action of relaxing bronchial smooth muscle is similar, but the role of the link is also different. The former increases.