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Erchen Wan (simplified Chinese: 二陈丸; traditional Chinese: 二陳丸) is a greyish-brown to yellowish-brown pill used in Traditional Chinese medicine to "remove damp-phlegm and regulate the stomach function". It is used in cases where there is "cough with copious expectoration, sensation of stuffiness in the chest and epigastrium, nausea and vomiting due to the stagnation of damp-phlegm". It is slightly aromatic in odour and tastes slightly pungent and sweet.
State Pharmacopoeia Commission of the PRC (2005). "Pharmacopoeia of The People's Republic of China (Volume I)". Chemical Industry Press. ISBN7-117-06982-1.