Zhong Gan Ling addresses blazing Heat or Fire at the Qi level, or at the Yang Ming channel, within the Six Stages. Heat if unresolved may traverse from the more superficial Greater Yang (Tai Yang) level, gather in intensity and strength and lodge in the deeper Yang Brightness (Yang Ming) level. In this pattern, the exterior invasion is beginning to penetrate the Qi level or the Yang Ming stage. It is accompanied by occasional discomfort in the neck and shoulders, aversion to heat and attraction to cold, a red face, occasional restlessness and irritability. All are indications of an invasion by an exterior influence that is generating a significant amount of Heat which is damaging to the Yin, and there may be accompanying signs of occasional insomnia, Five-Palms Heat and an occasional dry throat and a strong thirst. Zhong Gan Ling is appropriate when other “release the Exterior” protocols have not fully expelled Heat from the surface. It dispels Wind, clears Heat, drains blazing Fire, cools the Blood, and moistens the throat. The chief herbs in this formula are Kudzu root and Pubescent holly root. Together they comprise half of the formula by weight. Kudzu root discharges exterior invasion and releases the muscles, clears Heat, generates fluids, raises the Yang and addresses occasional loose bowels. Combined with Gypsum, it strongly abates Wind Heat. Pubescent holly root clears Heat, vents Fire at the Qi level, and invigorates the Blood. European verbena herb clears Heat, invigorates and cools the Blood, dispels stasis and supports healthy urination. Isatis root drains Heat, resolves blazing Fire, cools the Blood and benefits the throat. It has strong Heat dispelling actions and is indispensable for Heat invasions which have permeated from the Tai Yang to the Yang Ming level. Sweet wormwood herb clears all type of Yin level Heat without injuring the Qi, Blood or Yin, and cools the Blood. Gypsum clears heat, drains Fire from the Qi and Yang Ming levels, clears Heat from the Lungs and addresses Stomach Fire. Notopterygium root and rhizome releases the Exterior, dispels Wind Cold, dispels stagnation and guides the Qi to the Greater Yang channel and Governing vessels. It also guides the other herbs in the formula to the area served by these two channels. ORIGINS AND DEVELOPMENTZhong Gan Ling is a modern formulation based on many classical formulas, including White Tiger Decoction (Bai Hu Tang) from the Shang Ban Lun, and Bupleurum and Kudzu Decoction to Release the Muscle Layer (Chai Ge Jie Ji Tang).
