血虚身热有奇方。古有当归补血汤。五倍黄 归一分。（分。去声。黄 一两。当归二
钱五分。水煎服。）真阴濡布主之阳。
陈修园曰。凡轻清之药。皆属气分。味甘之药。皆能补中。黄 质轻而味微甘。故略能
补益。神农本草经。以为主治大风。可知其性矣。此方主以当归之益血。倍用黄 之轻清走
表者为导。俾血虚发热。郁于皮毛而不解者。仍从微汗泄之。故症象白虎。不再剂而热即如
失也。元人未读本经。此方因善悟暗合。其效无比。究之天之仁爱斯民特出此方。而假手于
元人。非元人识力所可到也。吴鹤皋以阳生阴长为解。亦是庸见。故特详之。
治气血虚弱之总方也。小儿惊。痘家虚甚。最宜。
补养诸汤首保元。参 桂草四般存。（黄 三钱。人参一钱。甘草一钱。肉桂春夏二分。
秋
气。
柯韵伯曰。保元者保守其元气之谓也。气。一而已。主肾。为先天真元之气。主胃。为
后天水谷之气者。此指发生而言也。又水谷之精气。行于经隧。为营气。水谷之悍气。行于
脉外。为卫气。大气之积于胸中而司呼吸者。为宗气。是分后天运用之元气而为三也。又外
应皮毛。协营卫而主一身之表者。为太阳膀胱之气。内通五脏。司治节而主一身之里者。为
太阴肺金之气。通内联外。应腠理而主一身之半表半里者。为少阳三焦之气。是以先天营运
之元气而为三也。此方用黄 和表。人参固里。甘草和中。三气治。而元气足矣。昔李东垣
以此三味。能泻火补金培土。为除烦热之圣药。镇小儿惊。效如桴鼓。魏桂岩得之。以治痘
家阳虚顶陷。血虚浆清。皮薄发痒。难灌难敛者。始终用之。以为血脱须补气。阳生则阴长。
有起死回生之功。故名之为保元也。又少佐肉桂。分四时之气而增损之。谓桂能治血。以推
动其毒。扶阳益气。以充达周身。血在内。引之出表。则气从内托。血外散。引之归根。则
气从外护。参 非桂引导。不能独树其功。桂不得甘草和平血气。亦不能绪其条理。要非浅
见寡闻者。能窥其万一也。四君中。不用白术。避其燥。不用茯苓。恐其渗也。用桂而不用
四物者。恶芎之辛散。归之湿润。芍之苦寒。地黄之泥滞故耳。如宜燥。则加苓术。宜润。
加归。除烦。加芍。散表。加芎。斯又当理会矣。
血虚引起的身体发热有一个奇特的方子。古代有当归补血汤。黄芪与当归的比例是五比一。（“分”读去声。黄芪一两，当归二钱五分，用水煎服。）此方以真阴的濡润布散为主来主导阳气。
陈修园说：凡是质地轻清的药材，都属于气分；味道甘甜的药材，都能补益中焦。黄芪质地轻而味道微甘，所以略能补益。《神农本草经》记载它主治大风，由此可知它的药性了。这个方子以当归的养血作用为主，重用黄芪的轻清走表之性作为引导，使得因血虚发热、郁结在皮毛而不能解除的病邪，仍然通过微微出汗的方式发散出去。所以症状表现像白虎汤证（大热、大汗、大渴、脉洪大），但不用两剂，热势就会消失。元代医家没有读过《神农本草经》，这个方子是因为善于领悟而暗合医理，其疗效无与伦比。究其根本，是上天仁爱百姓特意创制出这个方子，而假手于元人，并非元人的见识和力量所能达到的。吴鹤皋用“阳生阴长”来解释，这也是平庸的见解，所以我特别详细说明。
这是治疗气血虚弱总的方子。小儿惊风，痘疹患者正气极度虚弱时，最为适宜。
各种补养汤剂中首推保元汤。人参、桂枝、甘草四味药留存其中。（黄芪三钱，人参一钱，甘草一钱，肉桂根据春夏秋冬四季气候不同进行增减。）
柯韵伯说：所谓“保元”，就是保守元气的意思。气，只有一种，但功能不同。主司肾脏的是先天真元之气；主司胃腑的是后天水谷之气，这是从发生来源而言的。另外，水谷的精气，运行在经脉隧道中，称为营气；水谷的悍气，运行在脉管之外，称为卫气；积聚在胸中并主管呼吸的大气，称为宗气，这是将后天的运用之元气分为三类。另外，外应皮毛，协同营卫而主管一身之表的，是太阳膀胱之气；内通五脏，主管治理调节而一身之里的，是太阴肺金之气；贯通内外，对应腠理而主管一身半表半里的，是少阳三焦之气，这是将先天的营运之元气分为三类。这个方子用黄芪调和体表，用人参巩固体内，用甘草调和脾胃，三种气机得到调理，元气就充足了。以前李东垣认为这三味药，能泻火、补金、培土，是清除烦热的圣药，镇住小儿惊风，效果如敲鼓般迅速。魏桂岩得到此法，用来治疗痘疹患者阳气虚弱导致痘顶下陷、血虚导致浆液清稀、皮肤薄且发痒、难以灌浆和收敛的情况，始终使用此方，认为血脱必须补气，阳生则阴长，有起死回生的功效，所以命名为保元汤。又少量佐以肉桂，根据四季之气进行增减，说是肉桂能治血，以此推动毒邪外出，扶持阳气益气，使气血充达周身。血在内，引导它出于体表，则气从内部托举；血向外散，引导它归根，则气从外部护卫。人参如果没有肉桂的引导，就不能独自建立功效；肉桂如果没有甘草的平和血气作用，也不能理顺条理。这绝不是见识浅陋的人所能窥探到万一的。在四君子汤中，不用白术，是为了避开它的燥性；不用茯苓，是担心它的渗利作用。用肉桂而不用四物汤，是因为厌恶川芎的辛散、当归的湿润、芍药的苦寒、地黄的黏滞。如果适宜燥湿，则加茯苓、白术；适宜滋润，加当归；消除烦热，加芍药；发散表邪，加川芎，这些又应当深入理解。
There is a unique formula for body heat caused by blood deficiency. In ancient times, there was Danggui Buxue Tang (Danggui Decoction for Tonifying Blood). The ratio of Huangqi to Danggui is five to one. ("Fen" is pronounced with the falling tone. Huangqi 30g [1 liang], Danggui 7.5g [2 qian 5 fen], decocted in water.) This formula primarily governs Yang through the moistening and spreading action of True Yin.
Chen Xiuyuan stated: Any medicinal material that is light and clear belongs to the Qi aspect; any medicinal material with a sweet taste can tonify the Middle Jiao. Huangqi is light in texture and slightly sweet in taste, thus it can slightly tonify. According to the *Shennong Bencao Jing* (Divine Farmer's Materia Medica), its main indication is severe wind disorders, which reveals its nature. This formula takes Danggui's blood-nourishing effect as the principal agent, and uses the heavy dosage of Huangqi's light, clear, and exterior-wandering property as a guide. This allows the heat generated by blood deficiency, which is stagnant in the skin and hair follicles and unresolved, to be released through slight sweating. Therefore, although the symptoms resemble those of Baihu Tang syndrome (intense fever, profuse sweating, extreme thirst, and surging pulse), the heat disappears without even two doses. Yuan dynasty physicians had not read the *Shennong Bencao Jing*; this formula was effective because they intuitively grasped the underlying principles, achieving unparalleled results. Ultimately, it was Heaven's benevolence towards the people that specially created this formula, using Yuan physicians as instruments, rather than being within the scope of their own insight or capability. Wu Hegao explained it using the concept of "Yang generating Yin," which is also a mediocre view; therefore, I have detailed it specifically.
This is the general formula for treating Qi and Blood deficiency. It is most suitable for infantile convulsions and for patients with smallpox who are extremely deficient.
Among all nourishing decoctions, Baoyuan Tang (Preserve Origin Decoction) comes first. Ginseng, Guizhi, Gancao, and four other ingredients remain. (Huangqi 9g [3 qian], Renshen 3g [1 qian], Gancao 3g [1 qian], Rougui adjusted according to the seasonal Qi of spring/summer or autumn/winter.)
Ke Yunbo stated: "Baoyuan" means preserving the Primordial Qi. Qi is singular in essence but differs in function. The Qi governing the Kidney is the Pre-Heaven True Primordial Qi; the Qi governing the Stomach is the Post-Heaven Grain-derived Qi; this refers to their origin. Furthermore, the essence of grain and water that flows through the meridians is called Ying Qi (Nutritive Qi); the fierce Qi of grain and water that flows outside the vessels is called Wei Qi (Defensive Qi); the Great Qi accumulated in the chest that governs respiration is called Zong Qi (Gathering Qi). Thus, the Post-Heaven operational Primordial Qi is divided into three. Additionally, the Qi that externally corresponds to the skin and hair, cooperates with Ying and Wei Qi, and governs the exterior of the whole body is the Taiyang Bladder Qi; the Qi that internally connects to the Five Zang organs, governs regulation, and controls the interior of the whole body is the Taiyin Lung Metal Qi; the Qi that connects inside and outside, corresponds to the interstices, and governs the half-exterior/half-interior of the whole body is the Shaoyang Sanjiao Qi. Thus, the Pre-Heaven operational Primordial Qi is also divided into three. This formula uses Huangqi to harmonize the exterior, Renshen to consolidate the interior, and Gancao to harmonize the Middle Jiao. When these three Qi mechanisms are regulated, the Primordial Qi becomes sufficient. Previously, Li Dongyuan believed that these three herbs could purge fire, tonify Metal, and cultivate Earth, serving as a holy medicine for eliminating irritability and heat, effectively calming infantile convulsions like the rapid response of striking a drum. Wei Guiyan applied this method to treat smallpox patients with Yang deficiency causing depressed pustule tops, Blood deficiency causing thin pus, thin and itchy skin, and difficulty in filling and healing. He consistently used this formula, believing that when Blood is lost, Qi must be tonified, and when Yang generates, Yin grows, achieving the miracle of bringing the dead back to life. Hence, it is named Baoyuan. A small amount of Rougui is added as an assistant, adjusted according to the four seasons' Qi, stating that Guizhi treats Blood by pushing toxins out, supporting Yang and benefiting Qi to fill the entire body. If Blood is internal, guiding it to the surface causes Qi to support from within; if Blood disperses outward, guiding it to return to the root causes Qi to protect from without. Renshen cannot establish its merit alone without Guizhi's guidance; Rougui cannot organize its effects without Gancao's ability to harmonize Blood and Qi. This is certainly not something that someone with shallow knowledge can glimpse. In the Si Jun Zi Tang (Four Gentlemen Decoction), Baizhu is omitted to avoid dryness, and Fuling is omitted to prevent leakage. Rougui is used instead of Si Wu Tang (Four Substances Decoction) because one dislikes the acrid dispersion of Xiongqiong, the dampness of Danggui, the bitter cold of Shaoyao, and the cloying stagnation of Dihuang. If dryness is suitable, add Fuling and Baizhu; if moisture is suitable, add Danggui; to eliminate irritability, add Shaoyao; to disperse the exterior, add Xiongqiong. These points require further understanding.