Clinical Applications and Toxic Reactions of Asarum, September 5, 1996

Clinical Applications and Toxic Reactions of Asarum, September 5, 1996

Modern pharmacological research shows that Asarum has antipyretic, antibacterial, anti-inflammatory, bronchodilatory, antitussive, cardiotonic, sedative, anticonvulsant, analgesic, and local anesthetic effects. Overall, these can be summarized into four aspects: ① Anti-inflammatory and antipyretic; ② Antitussive and bronchodilatory; ③ Increasing heart rate; ④ Analgesic and promoting blood flow. How should we view the toxicity of this herb? Recent experimental studies show that this product contains volatile oil of Asarum, which first excites experimental animals and then suppresses them. Subsequently, respiratory and circulatory paralysis may occur, leading to death. The active ingredient of Asarum is methyl eugenol, while the toxic component is safrole. The latter is highly volatile, so prolonged boiling significantly reduces its toxicity without affecting the function of the active ingredient methyl eugenol. Therefore, some suggest that Asarum should be boiled for 30–60 minutes before being added to soups. Currently, China has 31 varieties, 4 subspecies, and 1 variant of Asarum. Among them, northern Asarum contains the highest proportion of methyl eugenol, about 40%, while southern Asarum is of poorer quality and has the lowest content of the active ingredient.