Pinellia ternata, also known as crow-dipper, is a plant native to China, Japan, and Korea. However, it also grows as an invasive weed in parts of Europe and North America. The leaves are trifoliate, and the flowers have a spathe and spadix form typical of plants in the family Araceae (Tian Nan Xing). This plant is commonly used in traditional Chinese medicine (TCM) for treating phlegm. Its Chinese name, Ban Xia (半夏: mid-summer), is derived from the fact that the plant sprouts and flowers around mid-summer, in June. The plant has a unique appearance, with peculiar leaves and flowers. Its English common name is green dragon, and its flower resembles a rising dragon or snake.
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| Green dragon flower |
Ban Xia has a warm temperature and an acrid taste. It enters the Spleen, Stomach, and Lung channels, and its typical dosage is 5-12g. Its actions include drying dampness and transforming phlegm, harmonizing the stomach and relieving vomiting, and dispersing stagnation and dissipating nodules. However, it is contraindicated for dry cough from yin deficiency, sore throat from fire excess, and bleeding. Unprocessed or overdose of Ban Xia can cause dry mouth, numbness of the tongue, and gastric discomfort. Ban Xia is used in several TCM formulas, such as Er Chen Tang, Wen Dan Tang, Ban Xia Xie Xin Tang, Ban Xia Hou Po Tang, and Ban Xia Bai Zhu Tian Ma Tang.
Since April 2004, Pinellia ternata has been banned in the US because it contains chemicals called ephedrine alkaloids. These chemicals might cause serious side effects such as heart attack, stroke, or seizures. The ban does not apply to traditional Asian medicines containing this ingredient. These products use Pinellia ternata tuber that has been processed to remove sharp crystals that can irritate the mouth, throat, and gut. It contains a stimulant called ephedrine. Ephedrine might cause serious side effects such as heart attack, stroke, or seizures. Due to these safety concerns, this product is banned in the U.S. Sedative medications (Barbiturates, Benzodiazepines, and CNS depressants) interact with Pinellia ternata. Pinellia ternata might cause sleepiness and drowsiness, and taking it along with sedative medications might cause excessive sleepiness. [4]
Recent research has shown that Pinellia ternata contains an average of 1.65μg/g of ephedrine. Even if the maximum daily dosage of 3-9g from the Chinese Pharmacopoeia is taken, it only equates to 0.01485mg, which is far below the World Anti-Doping Agency's (WADA) urinary ephedrine detection limit of 10μg/ml. In one study, it was reported that two-thirds of samples exceeded the 10μg/ml limit when 12mg of ephedrine was ingested. The 0.01485mg is only 1/828 of 12mg. Furthermore, excessive use of Ban Xia can cause hepatotoxicity and gastrointestinal toxicity, so it is not used in large quantities in clinical practice. In China, Japan, and Taiwan, TCM formulas containing Ban Xia, such as Ban Xia Hou Po Tang and Ban Xia Sha Shen Tang, are widely used, but they do not prohibit its usage [5] In traditional Chinese medicine, Ban Xia is processed with ginger to reduce toxicity, below is the picture of processed Ban Xia, which is often called Jiang Ban Xia.
Reference;
[1] Pinelliae Rhizoma Praeparatum cum Zingibere et Alumine could inhibit CYP3A activity. Conclusively, co-administration of PR with other CYP3A-metabolizing drugs may cause drug–drug interactions. Clinical use of PR-related formulae should be monitored carefully to avoid adverse interactions.
[2] Wu J, Cheng Z, He S, Shi J, Liu S, Zhang G, Zhu L, Liu L, Liu Z, Lin N, Lu L. Pinelliae rhizoma, a toxic chinese herb, can significantly inhibit CYP3A activity in rats. Molecules. 2015 Jan 7;20(1):792-806. doi: 10.3390/molecules20010792. PMID: 25574821; PMCID: PMC6272293.
[3] Seung Choi, Traditional Medicinal Herbology, second edition, ASIN : B08Z8D2RTG
[4] https://www.webmd.com/vitamins/ai/ingredientmono-1093/pinellia-ternata
[5] https://www.akomnews.com/bbs/board.php?bo_table=news&wr_id=29040