Alkaloids are a diverse group of naturally occurring compounds, many of which have been used in traditional medicine for respiratory support, particularly in the context of bronchial or pulmonary conditions. The use of alkaloid-containing plants, such as Lobelia inflata (Indian tobacco, containing lobeline) and Ephedra sinica (Ma Huang, containing ephedrine), has a long history in traditional herbal systems for supporting the bronchial system. These alkaloids have bronchodilatory and stimulant effects that can relieve bronchospasm and facilitate breathing. For example, ephedrine from Ephedra was historically used to treat asthma and bronchitis before the development of modern pharmaceuticals.

While some alkaloids have demonstrable pharmacological effects on the bronchial system, most evidence supporting their use is based on traditional practice rather than rigorous modern clinical trials. Additionally, many alkaloids can have significant side effects, and their therapeutic windows are narrow. Modern medicine has largely replaced these traditional remedies with safer, more standardized treatments, though some alkaloid derivatives (such as theophylline) are still used in respiratory medicine. In summary, the use of alkaloids for bronchial support is primarily justified by traditional use, with moderate pharmacological rationale but limited contemporary scientific validation.