Tongjing Wan (simplified Chinese: 痛经丸; traditional Chinese: 痛經丸) is a brownish-black pill used in Traditional Chinese medicine to "promote blood flow, dispel cold, regulate menstruation and relieve pain". It tastes slightly sweet and bitter. It is used where there is "abdominal pain during menstruation due to stagnation of blood by cold ". Tongjing Wan is to be taken before menstruation.
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Tongjing Wan Wikipedia(Text) CC BY-SA