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Siwu Tang Wan (simplified Chinese: 四物汤丸; traditional Chinese: 四物湯丸) is a brownish-black pill used in traditional Chinese medicine to "normalize menstruation and enrich blood". It is aromatic and tastes slightly sweet and bitter. It is used where there is "deficiency of blood, and irregular menstruation". The name Siwu Tang Wan literally means Pill of Four Substances in Chinese.
State Pharmacopoeia Commission of the PRC (2005). "Pharmacopoeia of The People's Republic of China (Volume I)". Chemical Industry Press. ISBN7-117-06982-1.
Long Zhixian, Li Qingye, Liu Zhanwen. "Formulas of Traditional Chinese Medicine" (方剂学 fāngjì xué), Academy Press (学苑出版社 xuéyuàn chūbǎnshè), Beijing University of Traditional Medicine. 2005. ISBN7-5077-1270-2.