柴胡∶味微苦，性平。禀少阳生发之气，为足少阳主药，而兼治足厥阴。肝气不舒畅者，此能舒之；胆
火甚炽盛者，此能散之；至外感在少阳者，又能助其枢转以透膈升出之，故《神农本草经》谓其主寒热，寒热者
少阳外感之邪也。又谓其主心腹肠胃中结气，饮食积聚，诚以五行之理，木能疏土，为柴胡善达少阳之木
气，则少阳之气自能疏通胃土之郁，而其结气饮食积聚自消化也。
《神农本草经》柴胡主寒热，山茱萸亦主寒热。柴胡所主之寒热，为少阳外感之邪，若伤寒疟疾是也，故
宜用柴胡和解之，山萸肉所主之寒热，为厥阴内伤之寒热，若肝脏虚极忽寒忽热，汗出欲脱是也，故宜用山萸
肉补敛之。二证之寒热虽同，而其病因判若天渊，临证者当细审之，用药慎勿误投也。
柴胡非发汗之药，而多用之亦能出汗。小柴胡汤多用之至八两，按今时分量计之，且三分之（古方一煎三
服，故可三分）一剂可得八钱。小柴胡汤中如此多用柴胡者，欲借柴胡之力升提少阳之邪以透膈上出也。然多
用之又恐其旁行发汗，则上升之力不专，小柴胡汤之去渣重煎，所以减其发汗之力也。
或疑小柴胡汤既非发汗之药，何以《伤寒论》百四十九节服柴胡汤后有汗出而解之语？不知此节文义，原
为误下之后服小柴胡汤者说法。夫小柴胡汤，系和解之剂，原非发汗之剂，特以误下之后，胁下所聚外感之邪，
兼散漫于手少阳三焦，因少阳为游部，手、足少阳原相贯彻也。此时仍投以小柴胡和解之，则邪之散漫于三焦
者，遂可由手少阳外达之经络作汗而解，而其留于胁下者，亦与之同气相求，借径于手少阳而汗解，故于发热
汗出上，特加一却字，言非发其汗而却由汗解也。然足少阳之由汗解原非正路，乃其服小柴胡汤后，胁下之邪
欲上升透膈，因下后气虚不能助之通过，而其邪之散漫于手少阳者，且又以同类相招，遂于蓄极之时而开旁通
之路，此际几有正气不能胜邪气之势，故必先蒸蒸而振，大有邪正相争之象，而后发热汗出而解，此即所谓战
而后汗也。观下后服柴胡汤者，其出汗若是之难，则足少阳之病由汗解，原非正路益可知也。是以愚生平临证，
于壮实之人用小柴胡汤时，恒减去人参，而于经医误下之后者，若用小柴胡汤必用人参以助其战胜之力。
用柴胡以治少阳外感之邪，不必其寒热往来也。但知其人纯系外感，而有恶心欲吐之现象，是即病在少阳，
欲借少阳枢转之机透膈上达也。治以小柴胡可随手奏效，此病机欲上者因而越之也。又有其人不见寒热往来，
亦并不喜呕，惟频频多吐粘涎，斯亦可断为少阳病，而与以小柴胡汤。盖少阳之去路为太阴湿土，因包脾之脂
膜原与板油相近，而板油亦脂膜，又有同类相招之义，此少阳欲传太阴，而太阴湿土之气经少阳之火铄炼，遂
凝为粘涎频频吐出，投以小柴胡汤，可断其入太阴之路，俾由少阳而解矣。又∶柴胡为疟疾之主药，而小心过
甚者，谓其人若或阴虚燥热，可以青蒿代之。不知疟邪伏于胁下两板油中，乃足少阳经之大都会，柴胡能入其
中，升提疟邪透膈上出，而青蒿无斯力也。若遇阴虚者，或热入于血分者，不妨多用滋阴凉血之药佐之；若遇
燥热者，或热盛于气分者，不妨多用润燥清火之药佐之。是以愚治疟疾有重用生地、熟地治愈者，有重用生石
膏、知母治愈者，其气分虚者，又有重用参、 治愈者，然方中无不用柴胡也。
【附案】一人年过四旬，胁下掀疼，大便七八日未行，医者投以大承气汤，大便未通而胁下之疼转甚。其
脉弦而有力，知系肝气胆火恣盛也，投以拙拟金铃泻肝汤加柴胡、龙胆草各四钱，服后须臾大便通下，胁疼顿
愈。审是，则《神农本草经》谓“柴胡主肠胃中饮食积聚，推陈致新”者，诚非虚语也。且不但能通大便也，
方书通小便亦多有用之者，愚试之亦颇效验。盖小便之下通，必由手少阳三焦，三焦之气化能升而后能降，柴
胡不但升足少阳实兼能升手少阳也。
柴胡：味道微苦，性质平和。它禀受了少阳生发之气，是足少阳胆经的主药，同时也能治疗足厥阴肝经的病症。肝气不舒畅时，它能疏解；胆火非常炽盛时，它能消散；至于外感病邪在少阳经的，它又能帮助枢机运转，使邪气透膈向上排出，所以《神农本草经》说它主治寒热，这里的“寒热”指的是少阳经的外感邪气。又说它主治心腹肠胃中的结气、饮食积聚，这是因为按照五行理论，木能疏土，柴胡善于通达少阳的木气，那么少阳之气自然能够疏通胃土的郁滞，其中的结气和饮食积聚自然也就消化了。
《神农本草经》记载柴胡主治寒热，山茱萸也主治寒热。柴胡所主的寒热，是少阳经的外感邪气，比如伤寒、疟疾等，所以适宜用柴胡来和解；山茱萸肉所主的寒热，是厥阴经的内伤寒热，比如肝脏虚极忽冷忽热、出汗欲脱等，所以适宜用山茱萸来补益收敛。这两种证候的寒热虽然相同，但病因截然不同，临床医生应当仔细审查，用药时千万不要误投。
柴胡不是发汗的药，但多用也能让人出汗。小柴胡汤中柴胡用量多达八两，按现在的分量计算，再除以三（古方一剂煎煮后分三次服用，所以可以除以三），一剂可得八钱。在小柴胡汤中如此大量使用柴胡，是想借助柴胡的力量升提少阳的邪气，使其透膈向上排出。然而，大量使用又担心它旁行导致发汗，这样上升的力量就不专一了，小柴胡汤要求去渣后重新煎煮，就是为了减少其发汗的力量。
有人怀疑小柴胡汤既然不是发汗的药，为什么《伤寒论》第149条说服用柴胡汤后有汗出而愈的说法？不知道这一条的文义，原本是为误用下法之后服用小柴胡汤的情况所说的。小柴胡汤是和解的药剂，原本就不是发汗的药剂，只是因为误用下法之后，聚集在胁下的外感邪气，兼散漫于手少阳三焦经，因为少阳经是游行之部，手、足少阳经原本是贯通的。此时仍然投以小柴胡汤来和解，那么散漫在三焦的邪气，就可以通过手少阳经的外达经络作汗而解，而留在胁下的邪气，也因为同气相求，借道于手少阳经而通过汗液排出，所以在“发热汗出”之上，特别加了一个“却”字，意思是并非通过发汗来驱邪，而是通过汗出而解。然而，足少阳经通过汗解原本不是正路，是因为服用小柴胡汤后，胁下的邪气想要上升透膈，但因为下法后气虚不能帮助邪气通过，而散漫在手少阳经的邪气，又以同类相招，于是在蓄积到极点时开辟了旁通之路，这时候几乎有正气不能战胜邪气的态势，所以必须先出现身体蒸蒸发热并颤抖，大有邪正相争的景象，然后才发热汗出而解，这就是所谓的“战而后汗”。观察误用下法后服用柴胡汤的人，出汗如此困难，那么足少阳经的病通过汗解，原本就不是正路，这一点就更加可以知道了。因此我平生临证，对于体质壮实的人使用小柴胡汤时，常常减去人参；而对于经过医生误用下法之后的人，如果使用小柴胡汤，必定用人参来帮助其战胜邪气的力量。
用柴胡来治疗少阳经的外感邪气，不一定非要见到寒热往来的症状。只要知道此人纯粹是外感，并且有恶心欲吐的现象，这就是病在少阳，想要借助少阳枢机运转的机制透膈向上达出。用小柴胡汤治疗可以随手奏效，这是病机想要向上的，就顺应它而越之（催吐或宣散）。又有的人不见寒热往来，也不喜欢呕吐，只是频繁地吐出粘稠涎沫，这也可以判断为少阳病，给予小柴胡汤。因为少阳的去路关联太阴湿土，包裹脾脏的脂膜原本与板油相近，而板油也是脂膜，又有同类相招的意义，这是少阳欲传变至太阴，而太阴湿土之气被少阳之火熏炼，于是凝结为粘涎频频吐出，投以小柴胡汤，可以切断其进入太阴的路径，使其由少阳经而解。另外，柴胡是治疗疟疾的主药，但小心谨慎过度的人，认为如果病人阴虚燥热，可以用青蒿代替。不知道疟邪潜伏在胁下两旁的板油中，那是足少阳经的大都会，柴胡能进入其中，升提疟邪透膈向上排出，而青蒿没有这种力量。如果遇到阴虚者，或者热入血分者，不妨多用滋阴凉血的药物辅助；如果遇到燥热者，或者热盛于气分者，不妨多用润燥清火的药物辅助。所以我治疗疟疾，有用重用生地、熟地治愈的，有用重用生石膏、知母治愈的，对于气分虚的，又有重用人参、[缺字，推测为党参或西洋参]治愈的，但在方剂中没有不用柴胡的。
【附案】一个人四十多岁，胁下红肿疼痛，大便七八天未行，医生给他用了大承气汤，大便没有通下来，而胁下的疼痛反而加重了。他的脉象弦而有力，知道是肝气、胆火恣意旺盛，投以我自己拟定的金铃泻肝汤，加入柴胡、龙胆草各四钱，服后不久大便通畅，胁痛立刻痊愈。审视这个案例，那么《神农本草经》说“柴胡主治肠胃中的饮食积聚，推陈致新”，确实不是空话。而且不仅能通大便，医书中治疗通小便也多有用到柴胡的，我尝试过也很有效验。大概小便的下通，必须经由手少阳三焦，三焦的气化功能能够升腾然后才能下降，柴胡不仅能升提足少阳，同时也兼能升提手少阳。
Chaihu (Bupleuri Radix): It has a slightly bitter taste and a neutral nature. Endowed with the ascending and generating qi of Shaoyang (Lesser Yang), it is the principal herb for the Foot-Shaoyang Gallbladder Meridian, while also treating disorders of the Foot-Jueyin Liver Meridian. When Liver Qi is not flowing smoothly, this herb can soothe it; when Gallbladder Fire is extremely blazing, this herb can disperse it; regarding external contraction pathogens located in the Shaoyang stage, it can further assist the pivot mechanism to facilitate the emergence of pathogens through the diaphragm upwards. Therefore, *Shennong Bencao Jing* (Divine Farmer's Materia Medica) states that it mainly treats chills and fever; here, "chills and fever" refer to the external pathogens affecting the Shaoyang meridian. It also states that it treats accumulated Qi in the heart, abdomen, intestines, and stomach, as well as food stagnation. This is indeed because according to the theory of Five Elements, Wood can loosen Earth. Chaihu excels at reaching the Wood Qi of Shaoyang; thus, the Qi of Shaoyang naturally unblocks the depression of Stomach Earth, and the accumulated Qi and food stagnation are naturally digested.
*Shennong Bencao Jing* records that Chaihu treats chills and fever, and Shanzhuyu (Corni Fructus) also treats chills and fever. The chills and fever treated by Chaihu are caused by external pathogens of the Shaoyang meridian, such as Shanghan (Cold Damage) or malaria, so it is appropriate to use Chaihu for harmonization. The chills and fever treated by Shanzhuyu Rou (the flesh of Corni Fructus) are caused by internal injury of the Jueyin meridian, such as extreme Liver deficiency leading to alternating cold and heat, and sweating with a sensation of collapse; therefore, it is appropriate to use Shanzhuyu for tonification and astringency. Although the chills and fever in these two conditions appear similar, their etiologies are worlds apart. Clinicians must examine carefully and must not prescribe erroneously.
Chaihu is not an herb for inducing sweating, but in large doses, it can cause sweating. In Xiao Chaihu Tang (Minor Bupleurum Decoction), the dose of Chaihu is up to eight liang. Calculated according to modern weights and divided by three (since ancient prescriptions were decocted once and taken in three servings), one prescription yields approximately eight qian. The reason for using such a large amount of Chaihu in Xiao Chaihu Tang is to borrow the power of Chaihu to lift and raise the Shaoyang pathogens so they may emerge through the diaphragm upwards. However, using large doses risks causing peripheral sweating, which would dilute the upward-lifting force. Therefore, the instruction in Xiao Chaihu Tang to strain the decoction and re-boil it serves to reduce its sweating-inducing potency.
One might doubt: if Xiao Chaihu Tang is not a sweating agent, why does Article 149 of *Shanghan Lun* (Treatise on Cold Pathogenic Diseases) state that after taking Chaihu Tang, the patient sweats and recovers? One should understand that the context of this article specifically addresses cases where Xiao Chaihu Tang is administered following an erroneous purgative treatment. Xiao Chaihu Tang is a harmonizing formula, not a sweating formula. However, after erroneous purgation, external pathogens gathered in the hypochondrium may scatter into the Hand-Shaoyang Sanjiao (Triple Burner). Since Shaoyang is a pathway for circulation, the Hand and Foot Shaoyang meridians are interconnected. At this point, administering Xiao Chaihu Tang for harmonization allows the pathogens scattered in the Sanjiao to exit via the exterior channels of the Hand-Shaoyang meridian through sweat. The pathogens remaining in the hypochondrium, seeking resonance with those in the Sanjiao, also take the path of the Hand-Shaoyang meridian to resolve via sweat. Hence, the term "que" (yet/instead) is added before "fever and sweating," indicating that recovery is achieved through sweating not by forcing sweat, but as a result of resolution. Nevertheless, resolution via sweating from the Foot-Shaoyang meridian is not the standard route. After taking Xiao Chaihu Tang, the pathogens in the hypochondrium desire to rise and emerge through the diaphragm, but due to Qi deficiency caused by purgation, they cannot pass easily. The pathogens scattered in the Hand-Shaoyang meridian attract each other, opening a collateral pathway when accumulation reaches its peak. At this moment, there is a tendency for Righteous Qi to be unable to overcome Pathogenic Qi. Thus, there is first a sensation of intense internal heat followed by trembling, showing a strong struggle between Righteous and Pathogenic Qi, before fever and sweating occur to resolve the condition. This is known as "shivering before sweating." Observing that patients who took Chaihu Tang after purgation found it difficult to sweat confirms that resolution via sweating from the Foot-Shaoyang meridian is indeed not the primary route. Therefore, in my clinical practice, when using Xiao Chaihu Tang for robust individuals, I often remove Renshen (Ginseng Radix et Rhizoma); however, for patients who have undergone erroneous purgation, if I use Xiao Chaihu Tang, I must include Renshen to assist the body's strength to overcome the pathogen.
When using Chaihu to treat external pathogens of the Shaoyang meridian, it is not necessary to observe alternating chills and fever. If one knows the patient suffers purely from external contraction and exhibits nausea with a desire to vomit, this indicates the disease is in the Shaoyang stage, seeking to ascend through the pivot mechanism of Shaoyang to emerge through the diaphragm. Treating with Xiao Chaihu Tang can yield immediate results; this follows the principle of treating upward-moving pathogenic mechanisms by dispersing them. In other cases, patients may not show alternating chills and fever nor dislike vomiting, but instead frequently spit out sticky saliva. This can also be diagnosed as a Shaoyang disease, treated with Xiao Chaihu Tang. This is because the pathway of Shaoyang relates to Taiyin Damp-Earth; the fatty membrane surrounding the Spleen is close to the visceral fat (ban you), which is also fatty tissue, implying an affinity of like substances. This represents Shaoyang attempting to transmit to Taiyin. The Damp-Earth Qi of Taiyin, refined by the Fire of Shaoyang, condenses into sticky saliva that is frequently spat out. Administering Xiao Chaihu Tang can block the path into Taiyin, allowing resolution via the Shaoyang meridian. Furthermore, Chaihu is the principal herb for malaria. Some overly cautious practitioners suggest substituting Qinghao (Artemisiae Annuae Herba) if the patient has Yin deficiency with dry-heat. They fail to realize that malaria pathogens lodge in the fatty tissues beneath the hypochondrium, the major hub of the Foot-Shaoyang meridian. Chaihu can enter this area and lift the malaria pathogens to emerge through the diaphragm, whereas Qinghao lacks this lifting power. For patients with Yin deficiency or Heat entering the Blood level, one may appropriately add herbs that nourish Yin and cool Blood; for those with Dry-Heat or Excess Heat in the Qi level, one may add herbs that moisten dryness and clear Fire. Thus, in my treatment of malaria, I have cured cases by heavily using Dihuang (Rehmanniae Radix, raw or prepared), Shigao (Gypsum Fibrosum), and Zhimu (Anemarrhenae Rhizoma); for Qi deficiency, I have used heavy doses of Renshen (Ginseng Radix et Rhizoma) [text missing, likely Dangshen or Xiyangshen]; yet in all formulas, Chaihu was indispensable.
[Attached Case]: A man over forty years old suffered from swelling and pain in the hypochondrium, with no bowel movement for seven or eight days. The physician prescribed Dachengqi Tang (Major Order the Qi Decoction). The bowels did not open, and the hypochondriac pain worsened. His pulse was wiry and forceful, indicating excessive Liver Qi and Gallbladder Fire. I prescribed Jinling Xiegan Tang (Goldbell Liver-Draining Decoction) formulated by myself, adding Chaihu and Longdancao (Gentianae Radix), four qian each. Shortly after ingestion, the bowels moved, and the hypochondriac pain ceased instantly. Examining this case, the statement in *Shennong Bencao Jing* that "Chaihu treats dietary accumulation in the intestines and stomach, pushing out the old and promoting the new" is indeed not empty words. Moreover, it not only promotes bowel movements; medical texts also frequently use it to promote urination. My trials have proven quite effective. Generally, the downward flow of urine must pass through the Hand-Shaoyang Sanjiao. The Qi transformation of the Sanjiao must ascend before it can descend. Chaihu not only lifts the Foot-Shaoyang but also assists in lifting the Hand-Shaoyang.