|Bàn Xià Gān Jiāng Sān|
|Bàn Xià||半夏||Equal amounts|
Discussion from the 100 Case Studies from the Jin Gui Yao Lue:
“Dry retching and vomiting with vomiting of saliva” is due to stomach Yang deficiency with cold fluids gathered on the interior. Bàn Xià Gān Jiāng Sān is Xiǎo Bàn Xià Tāng with Gān Jiāng replacing Shēng Jiāng. The aim of Xiǎo Bàn Xià Tāng is to stop vomiting and scatter fluids and so it uses Shēng Jiāng. The aim of this formula is to treat deficiency cold of the stomach Qi and the principle aim is to warm the middle. This is why this formula uses Gān Jiāng. The formula is a powder that is boiled in water to increase its function of regulating the middle and stopping vomiting.
Chapter 17 of the Jin Gui Yao Lue discusses “Pulses, Patterns and Treatment of Vomiting, Hiccough and Diarrhea.” Line 21 gives us the formula Bàn Xià Gān Jiāng Sān. This is the 3rd formula to use just the two herbs Ginger and Pinellia. It illustrates the difference between the use of Shēng Jiāng with Bàn Xià and Gān Jiāng with Bàn Xià. In the earlier formulas, there is vomiting due to fluids in the stomach. In this case the cold is more predominant, indicating the use of Gān Jiāng. Of course, Shēng Jiāng and Bàn Xià are both warming themselves and the indications for their use together does include the presence of thin fluids, i.e. cold fluids, in the stomach. So, what tells us that we should use Gān Jiāng instead of Shēng Jiāng? The clause itself gives us a clue:
“For dry retching, vomiting with counterflow, and droll foaming at the mouth, Bàn Xià Gān Jiāng Sānis indicated.”
Here, not only is there vomiting, there is also drool foaming at the mouth. This shows us that the cold is more extreme. In addition, there is dry retching. Why dry? When the fluids get cold enough, they freeze and this can cause dryness in the stomach. The same patho-phyisology is apparent with the use of Gan Cao Gan Jiang Tang for thirst.
From my own experience, there are a couple of other indications for using Gān Jiāng here: First, the presence of epigastric or abdominal pain that is better with warmth. Secondly, when tapping the stomach area, one hears a hollow tympanic sound rather than a watery sound. This sound often appears when the fluids have been frozen.
This combination of herbs is also found in the formulas Ban Xia Xie Xin Tang, Sheng Jiang Xie Xin Tang and Gan Cao Xie Xin Tang. In these formulas Gān Jiāng is used to open the middle. The pungent heat of Gān Jiāng is better at opening the blocked epigastric area than Shēng Jiāng would be. In addition it works to balance the bitter cold ingredients in these formulas.
In general, we can say that Gān Jiāng melts frozen fluids, stops pain and opens the middle, while stopping upward rebellion of the stomach.