Rehmannia 
Source: Beiji Qianjin Yaofang (Valuable Prescriptions for Emergencies).

Ingredients:
No.1  Shuiniujiao (Cornu Bubali) (originally Xijiao (Cornu Rhinocerotis) 30 g (decocted first)
No.2  Shengdihuang (Radix Rehmanniae) 24 g
No.3  Shaoyao (Radix Paeoniae) 12 g
No.4  Mudanpi (Cortex Moutan Radicis) 9 g

Administration:
Decoct the above drugs for oral use.

Actions:
Clearing away heat and toxin, cooling blood and removing blood stasis.

Clinical Application:
This recipe is indicated for syndrome of heat invading xuefen in the course of epidemic febrile diseases, marked by delirium, dark purple color of rashes; or syndrome of heat impairing the blood vessels as the result of miscellaneous diseases marked by haematemesis, epistaxis, hematochezia, hematuria, deep-red tongue with prickle-like fur, thready and rapid pulse. It is applicable to diffuse intravascular coagulation, urinaemia, purpura, acute leukemia, and hematosepsis that are attributable to excessive heat in xuefen. Ingredient No. 3 is now often clinically substituted for Chishaoyao (Radix Paeoniae Rubra).

If applied for excessive heat and toxin in xuefen manifesting coma and skin rashes, it is advisable to add Huanglian (Rhizoma Coptidis), Zhizi (Fructus Gardeniae) and Lianqiao (Fructus Forsythiae) to enhance the action of clearing away heat and toxin. In case of blood syndrome complicated with fire in the liver manifesting impetuosity and susceptibility to rage, add Chaihu (Radix Bupleuri), Zhizi (Fructus Gardeniae) to purge away fire in the liver. In case of heat combined with the accumulation of stagnated blood manifesting mania, add Dahuang (Radix et Rhizoma Rhei) and Huangqin (Radix Scutellariae) to expel heat and remove stasis.

Elucidation:
This syndrome results from heat invading xuefen, causing blood to flow uncontrollably and get stagnated, further giving rise to blood stasis. The method of clearing away heat to cool blood, and promoting the circulation of blood to remove blood stasis should be adopted. Ingredient No. 1 has the function of clearing away heat and toxin, cooling blood and stopping bleeding, acting as monarch drug. Ingredient No. 2 not only helps the monarch drug to carry out its function, but also nourishes yin and promotes the production of body fluid, acting as minister drug. The last two ingredients help the monarch and minister drugs on the one hand, and remove blood stasis and skin rashes on the other hand, serving as adjuvant drug.