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Zuojin Wan (Chinese: 左金丸) is a yellowish-brown pill used in Traditional Chinese medicine to "quench liver-fire, regulate the stomach function and relieve pain". Indications include an "attack of the stomach by liver-fire marked by epigastric and hypochondriac pain, bitterness in the mouth, heartburn and acid regurgitation, and a dislike for hot drinks".
Xubiao Luo, Bo Chen, Shouzhuo Yao. "Simultaneous analysis of protoberberine, indolequinoline and quinolone alkaloids in coptis–evodia herb couple and the Chinese herbal preparations by high-performance liquid chromatography–electrospray mass spectrometry", Talanta, Volume 66, Issue 1, 31 March 2005, Pages 103–110.