Source: Shanghan Lun (Treatise on Exogenous Febrile Diseases).

Ingredients:
No.1  Shigao (Gypsum Fibrosum) 50 g
No.2  Zhimu (Rhizoma Anemarrhenae) 18 g   
No.3  Zhigancao (Radix Glycyrrhizae Praeparatae) 6 g
No.4  Jingmi (Semen Oryzae Sativae) 9 g.
 
Administration:
Decoct the above drugs till the rice is well done and take the decoction several times after removal of the residue.

Actions:
Clearing away heat and promoting the production of body fluid.

Clinical Application:
This recipe is indicated for yangming meridian syndrome, marked by high fever, flushed face, polydipsia, profuse perspiration, aversion to heat, full forceful pulse. It is applicable to infectious diseases such as lobar pneumonia, epidemic encephalitis B, epidemic hemorrhagic fever, and gingivitis with the four characteristics of this syndrome (high fever, polydipsia, profuse perspiration, and full large pulse). In case of impairment of qi and body fluid due to excessive heat marked by full large but weak pulse, thirst not quenched with drink, add Renshen (Radix Ginseng) to replenish qi and promote the production of body fluid, forming another recipe entitled Baihu plus Renshen Tang.

In case of intense heat in both qifen and xuefen in combination with coma, delirium and skin rashes, add Shengdihuang (Radix Rehmanniae) and Shuiniujiao (Cornu Bubali) to clear away heat and cool the blood. In case of wind stirring up due to excessive heat concomitant with tic of limbs, add Lingyangjiao (Cornu Antelopis) and Gouteng (Ramulus Uncariae cure Uncis ) to relieve convulsion and spasm. In case of interior heat complicated with dampness, such as damp-warm syndrome with heat prevailing over dampness, or arthritis with reddish, swelling and painful joints, add Cangzhu (Rhizoma Atractylodis) to dry pathogenic dampness, constituting another recipe entitled Baihu plus Cangzhu Tang.

Elucidation:
This syndrome is the result of excessive heat in qifen scorching the body fluid, and should be treated by clearing away heat and promoting the production of body fluid. Ingredient No. 1, pungent and sweet in flavor and extremely cold in property, acts as monarch drug, capable of purging away heat without impairing body fluid. Ingredient No. 2, which is bitter in flavor and cold moist in property, serves as minister drug, strengthening the action of the monarch drug and promoting the production of body fluid as well. Ingredients No. 3 and No. 4 function as adjuvant drug that can not only reinforce the stomach and protect body fluid, but also prevent the stomach from being injured by the extremely cold drug as ingredient No. 1. Besides, No. 3 also plays the role of guiding drug, mediating drug properties.

Cautions:
This must not be applied to patients with full large but weak pulse when pressed and pale tongue, which are attributable to fever due to blood deficiency.