Xiao Chai Hu Tang 小 柴 胡 湯
Si Ni San 四 逆 散
Xiao Yao San 逍 遙 散
Ban Xia Xie Xin Tang 半 夏 瀉 心 湯
Source: Discussions of Cold Damage (c. 220)
Indication: Yang-type inversion due to internal Qi constraint
Symptoms: Cold fingers and toes with a warm head and body, sometimes accompanied by a sensation of irritabiity and fullness in the chest adn epigastrium.
There may also be abdominal pain and/or severe diarrhea (Liver-Spleen disharmony).
Tongue: red, yellow coat; Pulse: wiry
The focus of this formula is to regulate qi by venting heat and releasing constraint, this is seen in how cool/cold the formula is. In addition, it is very bitter and drains stagnation resulting in effective qi regulation.