Qing Hao Bie Jia Tang is a fascinating formula because it draws upon an interesting combination of medicinals.  The heavy, sinking nature of Bie Jia guides the formula deep into the interior while the light Qing Hao outthrusts heat.  The formula was originally designed for the advanced stages of warm disease, with latent (deep-lying) evil in the yin aspect.

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This textbook pattern for Qing Hao Bie Jia Tang manifests in nighttime heat that abates by the morning.  The heat abates in the absence of sweating, and there is a red tongue with scant liquid and a thin rapid pulse.

Ingredients

Qing Hao (Artemisiae Annuae Herba)

Bie Jia (Trionycis Carapax)

Mu Dan Pi (Moutan Cortex)

Sheng Di Huang (Rehmanniae Radix)

Zhi Mu (Anemarrhenae Rhizoma)

Actions:This formula nourishes yin and outthrusts heat.

Ingredient breakdown:

Bie Jia directly enters the yin aspect to abate vacuity heat, and also enters the network vessels to track down evil. Qing hao clears heat and outthrusts the network vessels, guiding evil outward. Both are sovereign medicinals.

The combination of these two medicinals inspired the following statement in the Wen Bing Tiao Bian:
“[It] has the mystery of first entering and later exiting.  Qing Hao cannot directly enter the yin aspect, so Bie Jia leads it in.  Bie Jia alone cannot exit to the yang aspect, so Qing Hao leads it out.”

Sheng Di Huang enriches yin, clears heat, and cools the blood, while Zhi Mu enriches yin and downbears fire.  Both are ministers that help Bie Jia to nourish yin and abate vacuity heat.  Mu Dan Pi is an assistant; it drains latent fire within yin, and helps Qing Hao to clear and outthrust latent heat in the yin aspect.  When fire abates, yin is engendered on its own.

This formula has few ingredients yet it illustrates unique principles and has an eloquent construction.