论曰∶寒热之病，或寒已而热，或热已而寒，或寒热战栗，头痛如破，身体拘急，数欠
渴欲饮冷，或 时而发，或间日而作，至期便发，发已即如常，此谓之疟。疟脉自弦，弦
多热，弦迟多寒。此皆得之于冬中风寒之气，藏于骨髓之中，至春阳气大发，邪气不能自
因遇大暑，而后与邪气相合而发，常山汤主之。
常山汤
常山 知母 甘草（炙，各三两） 麻黄（去节，一两）
上为散。每服五钱，水二盏，煎至一盏，去滓温服。以糜粥一杯，助取汗为度。
热多者宜解之，栝蒌汤主之。
栝蒌汤
栝蒌根（四两） 柴胡（去苗，八两） 人参 黄芩 甘草（炙，各三两）
上为末。每服二钱，水二盏，生姜三片，枣一个，擘开，煎至一盏，去滓温服。
寒多者宜温之，姜桂汤主之。
姜桂汤
干姜 牡蛎（火 通赤） 甘草（炙，各二两） 黄芩（二两，《活人书》用三两） 柴
胡（
去苗，八两） 栝蒌根（四两） 桂（去皮取心，三两）
上为末。每服五钱，水二盏，煎至一盏，去滓温服，不拘时候。
寒热等者宜调之，鳖甲汤主之。
鳖甲汤
鳖甲（汤浸，刮令净，醋炙） 白术 常山 桂（去皮） 柴胡（去苗，各一两） 牡
蛎（半
两，火 赤）
上为散。每服五钱，水二盏，煎至一盏，去滓温服。
It is stated: Diseases characterized by alternating chills and fever, where coldness subsides followed by heat, or heat subsides followed by coldness, or accompanied by shivering and trembling, severe headache as if the head were splitting, bodily stiffness and tension, frequent yawning, thirst with a desire to drink cold water, occurring either at fixed times or every other day, manifesting precisely when due and resolving to normalcy immediately after onset, are termed Malaria (Nüe). The pulse of Malaria is naturally Xian (String-taut pulse). A predominantly Xian pulse indicates Heat; a Xian and Chi (Slow) pulse indicates Cold. These conditions arise from Wind-Cold pathogens contracted in winter, which lodge within the Marrow. In spring, when Yang Qi expands vigorously, the pathogenic factor cannot dissipate on its own. If encountered with intense summer heat, it combines with the pathogen to trigger an attack, primarily treated with Changshan Tang (Changshan Decoction).
Changshan Tang (Changshan Decoction)
Dichroa Radix (Changshan), Anemarrhenae Rhizoma (Zhimu), Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (Zhi Gancao, each 3 liang), Ephedrae Herba (Mahuang, de-segmented, 1 liang).
The above ingredients are processed into a powder. Each dose consists of 5 qian, decocted in 2 zhan of water until reduced to 1 zhan. Strain the dregs and take warm. Follow with one cup of millet gruel to assist in inducing sweating as the goal.
When Heat predominates, it should be resolved with Gualou Tang (Gualou Decoction).
Gualou Tang (Gualou Decoction)
Trichosanthis Radix (Gualougen, 4 liang), Bupleuri Radix (Chaihu, de-radicle, 8 liang), Ginseng Radix (Renshen), Scutellariae Radix (Huangqin), Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (Zhi Gancao, each 3 liang).
The above ingredients are ground into fine powder. Each dose consists of 2 qian, decocted with 2 zhan of water, 3 slices of Zingiberis Rhizoma Recens (Shengjiang), and one Jujubae Fructus (Zao, split open) until reduced to 1 zhan. Strain the dregs and take warm.
When Cold predominates, it should be warmed with Jianggui Tang (Jianggui Decoction).
Jianggui Tang (Jianggui Decoction)
Zingiberis Rhizoma (Ganjiang), Ostrea Concha (Muli, fired until red-hot), Glycyrrhizae Radix et Rhizoma Praeparata cum Melle (Zhi Gancao, each 2 liang), Scutellariae Radix (Huangqin, 2 liang; 3 liang in *Liuren Shu*), Bupleuri Radix (Chaihu, de-radicle, 8 liang), Trichosanthis Radix (Gualougen, 4 liang), Cinnamomi Ramulus (Gui, bark removed, heart taken, 3 liang).
The above ingredients are ground into fine powder. Each dose consists of 5 qian, decocted in 2 zhan of water until reduced to 1 zhan. Strain the dregs and take warm, without restriction on time.
When Chills and Heat are equal, they should be harmonized with Biejia Tang (Biejia Decoction).
Biejia Tang (Biejia Decoction)
Testudinis et Carapax et Plastrum (Biejia, soaked in hot water, scraped clean, vinegar-fried), Atractylodis Macrocephalae Rhizoma (Baizhu), Dichroa Radix (Changshan), Cinnamomi Ramulus (Gui, bark removed), Bupleuri Radix (Chaihu, de-radicle, each 1 liang), Ostrea Concha (Muli, 0.5 liang, fired until red-hot).
The above ingredients are processed into a powder. Each dose consists of 5 qian, decocted in 2 zhan of water until reduced to 1 zhan. Strain the dregs and take warm.