发热恶寒。多是外感伤其荣卫。伤荣则寒。伤卫则热。平人治法。须用麻桂发散。失血皆阴血大亏。不可再
汗。以耗其气分之水液。只可用小柴胡汤。加荆芥防风紫苏杏仁薄荷前胡葛根等。以和散之。免犯仲景
血家忌汗之戒也。若不关外感。系本身荣卫不和。发为寒热。似疟非疟者。不可作疟治之。只用小柴胡。或
逍遥散。和其荣卫而愈。又有瘀血作寒热者。其身必有刺痛之处。血府逐瘀汤治之。此与杂病寒热有异。
医者须知。
汗者。气分之水也。血虚则气热。故蒸发其水。而出为汗。但头汗出。身不得汗者。乃阳气内郁。冒于下而为
汗。以小柴胡汤。解其郁。则通身得汗而愈。蒸蒸汗出者。乃血虚气盛。沸溢为汗。宜用白虎汤。加当归蒲黄
蝉蜕治之。手足 汗出者。以胃中或有瘀血食积。四肢为中州之应。火热中结。故应手足汗出也。宜玉
烛散。加枳壳浓朴以攻之。结去而汗自止矣。睡中盗汗者。睡则气归血分。血不足则气无所归。故气泄而
汗出。宜当归六黄汤治之。或地骨皮散。加枣仁知母茯苓五味子黄 黄柏。
以上所论。皆失血家阴血内虚。阳气遏发之病。亦有阴阳两虚。自汗盗汗者。宜归脾汤加麦冬五味子。或
当归六黄汤加附子。
又有大汗亡阳者。在杂病亡阳。则单属阳虚。失血家大汗亡阳。则兼是阴虚。阳无所附。非大剂参附汤。不
能回阳。继用独参汤养之而愈。
此论血家出汗。与杂证出汗有别。参看汗血发热门更详。
发热且恶寒，多是因为外感邪气损伤了营卫。损伤营分则表现为寒，损伤卫分则表现为热。对于普通人，治疗方法需要使用麻黄汤或桂枝汤来发散邪气；但失血患者由于阴血严重亏损，不可再次发汗，以免耗伤气分中的水液。此时只可用小柴胡汤，加入荆芥、防风、紫苏、杏仁、薄荷、前胡、葛根等药物，以调和并疏散邪气，从而避免触犯张仲景关于失血者忌用发汗法的禁忌。
如果并非由外感引起，而是自身营卫不和，导致出现寒热交替，症状类似疟疾但非疟疾者，不可按疟疾治疗。只需使用小柴胡汤，或者逍遥散，调和营卫即可痊愈。又有因瘀血导致寒热交替的情况，其身体必有刺痛之处，可用血府逐瘀汤治疗。这与杂病中的寒热有所不同，医生必须知晓。
汗，是气分中的水液。血虚则气热，因此蒸发水液而排出为汗。如果只有头部出汗，身体无汗，这是阳气内郁，郁结于下所致，可用小柴胡汤解除郁滞，则全身得汗而愈。如果是蒸蒸而出的大汗，则是血虚气盛，气血沸腾溢出为汗，适宜用白虎汤，加入当归、蒲黄、蝉蜕治疗。手足心出汗，是因为胃中可能有瘀血或食积，四肢对应中焦脾胃，火热在中焦结聚，所以应手足出汗，适宜用玉烛散，加入枳壳、厚朴以攻逐实邪，结滞去除后汗自然停止。睡中盗汗，是因为睡觉时气归于血分，血不足则气无所依附，所以气泄而汗出，适宜用当归六黄汤治疗，或者用地骨皮散，加入酸枣仁、知母、茯苓、五味子、黄芪、黄柏。
以上所论述的，都是失血患者阴血内虚，阳气被遏而发热的病症。也有阴阳两虚，出现自汗和盗汗的情况，适宜用归脾汤加入麦冬、五味子，或者用当归六黄汤加入附子。
又有因大汗导致亡阳的情况，在杂病中亡阳单纯属于阳虚，但在失血患者中大汗亡阳则兼有阴虚，阳气无所依附，非大剂量参附汤不能回阳，随后再用独参汤调养即可痊愈。
此论失血患者的出汗，与杂证患者的出汗有别，参考“汗血发热”篇更为详细。
Fever accompanied by aversion to cold is mostly caused by external pathogens damaging the Ying (Nutritive) and Wei (Defensive) levels. Damage to the Ying level manifests as cold, while damage to the Wei level manifests as heat. For healthy individuals, the treatment method requires using Mahuang Tang (Ephedra Decoction) or Guizhi Tang (Cinnamon Twig Decoction) to disperse the pathogen. However, patients with blood loss suffer from a severe deficiency of Yin blood and must not undergo diaphoresis (sweating therapy), as this would consume the fluids in the Qi level. Instead, Xiaochaihu Tang (Minor Bupleurum Decoction) should be used, augmented with Jingjie (Schizonepetae Herba), Fangfeng (Saposhnikoviae Radix), Zisu Ye (Perillae Folium), Xingren (Armeniacae Semen Amarum), Bohe (Menthae Haplocalycis Herba), Qianhu (Peucedani Radix), and Gegen (Puerariae Lobatae Radix), to harmonize and disperse the pathogen, thereby avoiding violating Zhang Zhongjing's prohibition against diaphoresis in patients with blood loss.
If the condition is not related to external contraction but stems from internal disharmony of Ying and Wei, resulting in alternating chills and fever that resemble malaria but are not malaria, it should not be treated as malaria. One should simply use Xiaochaihu Tang (Minor Bupleurum Decoction) or Xiaoyao San (Free and Easy Wanderer Powder) to harmonize the Ying and Wei, leading to recovery. There are also cases where blood stasis causes alternating chills and fever; in such cases, there must be stabbing pain in specific areas of the body, which can be treated with Xuefu Zhuyu Tang (Blood Mansion Stasis-Expelling Decoction). This differs from chills and fever in miscellaneous diseases, and physicians must be aware of this distinction.
Sweat is the fluid within the Qi level. When blood is deficient, Qi becomes hot, thus evaporating the fluid and expelling it as sweat. If only the head sweats while the body remains dry, this indicates internal stagnation of Yang Qi, constrained below; Xiaochaihu Tang (Minor Bupleurum Decoction) should be used to resolve the stagnation, after which general sweating will occur and the patient will recover. Profuse, steaming sweat indicates that blood deficiency has led to excessive Qi, causing boiling and overflow into sweat; Baihu Tang (White Tiger Decoction) augmented with Danggui (Angelicae Sinensis Radix), Puhuang (Typhae Pollen), and Chantui (Cicadae Periostracum) is appropriate. Sweating on the hands and feet suggests blood stasis or food retention in the Stomach; since the four limbs correspond to the Middle Jiao (Central Region), fire-heat knotting in the center leads to sweating on the extremities. Yuzhu San (Jade Candle Powder) augmented with Zhike (Aurantii Fructus) and Houpo (Magnoliae Officinalis Cortex) should be used to attack and remove the accumulation; once the knot is resolved, sweating will cease spontaneously. Night sweats (stealing sweat) occur because during sleep, Qi returns to the Blood level; if Blood is insufficient, Qi has no place to reside and thus leaks out as sweat. Danggui Liu Huang Tang (Six-Huang Decoction with Angelica) is suitable for treatment, or Digupi San (Digupi Powder) augmented with Zaoren (Ziziphi Spinosae Semen), Zhimu (Anemarrhenae Rhizoma), Fuling (Poria), Wuweizi (Schisandrae Chinensis Fructus), Huangqi (Astragali Membranacei Radix), and Huangbai (Phellodendri Cortex).
The above discussions all pertain to illnesses in patients with blood loss characterized by internal deficiency of Yin blood and the suppression and eruption of Yang Qi. There are also cases of spontaneous sweating and night sweats due to dual deficiency of Yin and Yang; in such cases, Guipi Tang (Restore the Spleen Decoction) augmented with Maidong (Ophiopogonis Radix) and Wuweizi (Schisandrae Chinensis Fructus), or Danggui Liu Huang Tang (Six-Huang Decoction with Angelica) augmented with Fuzi (Aconiti Lateralis Radix Praeparata), is appropriate.
There are also cases of massive sweating leading to collapse of Yang (Wang Yang). In miscellaneous diseases, collapse of Yang belongs purely to Yang deficiency; however, in patients with blood loss, massive sweating leading to collapse of Yang involves both Yin and Yang deficiency, where Yang has no anchor. Only a large dose of Shenfu Tang (Ginseng and Aconite Decoction) can restore Yang, followed by Dushen Tang (Single Ginseng Decoction) for nourishment until recovery.
This discussion on sweating in patients with blood loss differs from sweating in miscellaneous syndromes; refer to the chapter on "Sweat, Blood, and Fever" for more details.