少阳寒热往来频。口苦咽干胁下疼。目眩耳聋头角痛。小柴汤是顶门针。
按伤寒三四日内。及足少阳胆经受之。其脉起于目锐 。瞳子 骨、上头角、络耳、循
胸、胁、行身之侧。终于足四指之窍阴穴也。其症则胸胁满而耳聋。往来寒热。然少阳
为半表半里。其脉尺寸俱弦。弦而数者。病在中也。宜小柴胡汤和之。凡治有三禁。不可发
汗。发汗则谵语。不可吐下。吐下则悸而惊。只宜和之。以柴胡汤。至病患呕而不渴。加半
夏。渴而作呕。加姜汁竹茹。或渴或不渴。或呕或不呕。在随症而加减之。
小柴胡汤 五般。半夏人参共交攒。更有黄芩与甘草。生姜枣子水同煎。
三阳传罢入三阴。转入阴经势转深。若是阴经名直中。沉寒锢冷却宜温。
所以三阴有传经直中之不常。须究脉理而推详。传经者。脉沉数而烦热。直中者。脉沉
阳邪传入太阴经。腹满咽干手足温。尺寸俱沉时常数。桂枝加入大黄平。
按伤寒四五日内。乃足太阴脾经受之。其脉起于手足大指之隐白穴。上行至腹。络于嗌
。连舌本。行身之前。终于大包穴也。其症则腹满或痛。咽干自利。然三阳为表。三阴为里
。其脉尺寸俱沉。沉而有力。传经热症也。宜桂枝加大黄汤下之。沉而无力。直中寒症也。宜
理中四逆汤温之。若本是阳症。或重受风寒。或过食生冷。或误服凉药。遂变成阴症。此为
害热未已。寒病复起。始病热症。末传寒中也。亦宜理中四逆汤温之。他如伤寒入三阴。尚
有在经表邪。如太阴有桂枝加芍药汤。少阴有麻黄附子细辛汤。厥阴有当归四逆汤之类。皆
阴经表药也。
当归四逆汤
当归 白芍 桂枝 细辛 通草 甘草 大枣
桂枝大黄甘草芍。枳实柴胡姜枣着。槟榔大腹用水煎。太阴实热须臾却。桂枝加芍减甘
草。更用生姜及大枣。表症未除因误下。太阴腹痛斯安好。
少阳经的病证表现为寒热往来，发作频繁。伴有口苦、咽干、胁肋部疼痛。出现目眩、耳聋、头角疼痛。小柴胡汤是治疗此病的特效方剂（顶门针）。
按：伤寒病在三四日内，邪气传入足少阳胆经。该经脉起于目外眦（锐眦），经过瞳子髎穴、头部侧面，联络耳部，循行于胸胁部，沿身体两侧下行，终于足第四趾外侧端的窍阴穴。其症状表现为胸胁胀满、耳聋、寒热往来。因为少阳经位于半表半里之间，其脉象寸关尺三部均呈弦象。若弦而兼数，说明病邪在里。适宜用小柴胡汤进行和解治疗。凡是治疗少阳病有三项禁忌：不可发汗，发汗会导致谵语；不可催吐或泻下，吐下会导致心悸和惊恐。只宜采用和解法，使用柴胡汤类方剂。如果患者呕吐但不口渴，加入半夏；如果口渴且呕吐，加入姜汁和竹茹。或者不渴或不呕的情况，应根据具体症状进行加减调整。
小柴胡汤由五味药组成：半夏、人参共同配伍。还有黄芩和甘草，加上生姜和大枣用水同煎。
三阳经的病证传变完毕后进入三阴经，转入阴经后病情势态加深。如果是阴经的“直中”证，属于沉寒内盛，冷却适宜用温法治疗。
所以三阴经有传经和直中两种不同的情况，必须探究脉理来详细推究。传经者，脉象沉数且伴有烦热；直中者，脉象沉……（原文此处中断）
阳邪传入太阴经，症状为腹部胀满、咽干、手足温暖。寸关尺脉象均沉，时常兼数。适宜用桂枝加大黄汤平调。
按：伤寒病在四五日内，邪气传入足太阴脾经。该经脉起于足大趾内侧端的隐白穴，上行至腹部，联络咽喉，连接舌根，行于身体前面，终于大包穴。其症状表现为腹部胀满或疼痛、咽干、自发性腹泻。因为三阳经属表，三阴经属里。其脉象寸关尺三部均呈沉象。若沉而有力，属于传经热症，适宜用桂枝加大黄汤攻下。若沉而无力，属于直中寒症，适宜用理中汤或四逆汤温补。如果原本是阳证，又重感风寒，或过食生冷，或误服凉药，遂转变为阴证。此为热病未愈，寒病又起。开始是热证，最后传变为寒中。也适宜用理中汤或四逆汤温补。其他如伤寒传入三阴，尚有在经表的邪气，例如太阴经有桂枝加芍药汤，少阴经有麻黄附子细辛汤，厥阴经有当归四逆汤之类，这些都是治疗阴经表证的方药。
当归四逆汤
药材包括：当归、白芍、桂枝、细辛、通草、甘草、大枣。
桂枝大黄甘草芍药，枳实柴胡生姜大枣配合。槟榔、大腹皮用水煎煮。太阴实热证可迅速消除。桂枝加芍药汤减去甘草，再加生姜和大枣。用于表证未除因误用下法导致的太阴腹痛，以此方可安好。
Shaoyang (Lesser Yang) disease manifests as alternating chills and fever, occurring frequently. Accompanying symptoms include bitter taste in the mouth, dry throat, and pain in the hypochondriac region. Dizziness, deafness, and pain at the temporal angle are also present. Xiaochaihu Tang (Minor Bupleurum Decoction) is the premier remedy for this condition.
Note: In Shanghan (Cold Damage) disease, within three to four days, the pathogen enters the Foot-Shaoyang Gallbladder Meridian. This meridian originates from the outer canthus of the eye, passes through Tongziliao (GB1), ascends to the temporal angle, connects with the ear, follows the chest and hypochondrium, runs along the lateral aspect of the body, and terminates at the Qiaoyin point (GB44) on the lateral side of the fourth toe. The clinical manifestations include fullness in the chest and hypochondrium, deafness, and alternating chills and fever. Since Shaoyang is located between the exterior and interior, the pulse is wiry (Xian) across all three positions (Cun, Guan, Chi). If the pulse is wiry and rapid (Shu), it indicates the pathogen is in the interior. It is appropriate to use Xiaochaihu Tang to harmonize. There are three prohibitions in treating Shaoyang disease: sweating (Fa Han) is contraindicated, as it may lead to delirious speech; emesis (Tu) and purgation (Xia) are contraindicated, as they may cause palpitations and fright. Only harmonization should be employed, using Bupleurum-based formulas. If the patient vomits without thirst, add Banxia (Pinelliae Rhizoma); if there is thirst accompanied by vomiting, add Jiangzhi (Ginger Juice) and Zhuru (Bambusae Caulis in Taenia). Adjustments should be made according to specific symptoms, whether or not there is thirst or vomiting.
Xiaochaihu Tang consists of five ingredients: Banxia (Pinelliae Rhizoma) and Renshen (Panacis Ginseng Radix) are combined. Huangqin (Scutellariae Radix) and Gancao (Glycyrrhizae Radix et Rhizoma) are added, along with Shengjiang (Zingiberis Rhizoma Recens) and Zao (Jujubae Fructus), decocted together in water.
After the transmission through the Three Yang meridians is completed, the disease enters the Three Yin meridians, where the pathological state deepens. If it is a "direct strike" (Zhi Zhong) into the Yin meridians, characterized by severe cold accumulation, warming methods are appropriate.
Therefore, the Three Yin meridians have two distinct patterns: transmitted heat and direct strike cold. One must investigate the pulse principles for detailed differentiation. In transmitted cases, the pulse is deep (Chen) and rapid (Shu), accompanied by irritability and heat. In direct strike cases, the pulse is deep... [text cuts off]
When Yang pathogenic factors transmit to the Taiyin Meridian, symptoms include abdominal fullness, dry throat, and warm hands and feet. The pulse is deep (Chen) at all positions, often with a rapid (Shu) quality. Guizhi Jada Huang Tang (Cinnamon Twig plus Rhubarb Decoction) is suitable for regulation.
Note: In Shanghan disease, within four to five days, the pathogen enters the Foot-Taiyin Spleen Meridian. This meridian originates from the Yinbai point (SP1) on the medial side of the big toe, ascends to the abdomen, connects with the pharynx, links to the root of the tongue, runs along the anterior aspect of the body, and terminates at the Dabao point (SP21). Symptoms include abdominal fullness or pain, dry throat, and spontaneous diarrhea. Since the Three Yang meridians belong to the exterior and the Three Yin meridians to the interior, the pulse is deep (Chen) across all positions. If the pulse is deep and forceful, it indicates transmitted heat syndrome, suitable for purgation with Guizhi Jada Huang Tang (Cinnamon Twig plus Rhubarb Decoction). If the pulse is deep and weak, it indicates direct strike cold syndrome, suitable for warming with Lizhong Tang (Regulate the Middle Decoction) or Sini Tang (Frigid Extremities Decoction). If the original condition was Yang syndrome, but the patient suffered heavy wind-cold exposure, overconsumed raw/cold food, or mistakenly took cooling medicines, it transforms into a Yin syndrome. This represents residual heat coexisting with new cold. Starting as heat, it ultimately transmits to cold in the middle jiao. Warming with Lizhong Tang (Regulate the Middle Decoction) or Sini Tang (Frigid Extremities Decoction) is also appropriate. Other examples of Shanghan entering the Three Yin meridians with exterior pathogens remaining in the meridian include Guizhi Jiabaishao Tang (Cinnamon Twig plus White Peony Decoction) for Taiyin, Mahuang Fuzi Xixin Tang (Ephedra, Aconite, and Asarum Decoction) for Shaoyin, and Danggui Sini Tang (Angelica Sinensis Decoction for Cold-Reversal) for Jueyin. These are formulas for treating exterior conditions in Yin meridians.
Danggui Sini Tang (Angelica Sinensis Decoction for Cold-Reversal)
Ingredients: Danggui (Angelicae Sinensis Radix), Baishao (Paeoniae Radix Alba), Guizhi (Cinnamomi Ramulus), Xixin (Asari Radix et Rhizoma), Tongcao (Tetrapanacis Medulla), Gancao (Glycyrrhizae Radix et Rhizoma), Dazao (Jujubae Fructus).
Guizhi (Cinnamon Twig), Da Huang (Rhei Radix et Rhizoma), Gancao (Glycyrrhizae Radix et Rhizoma), and Baishao (Paeoniae Radix Alba) are used. Zhishi (Aurantii Fructus Immaturus), Chaihu (Bupleuri Radix), Shengjiang (Zingiberis Rhizoma Recens), and Dazao (Jujubae Fructus) are added. Binlang (Arecae Semen) and Dafupi (Tsaoko Pericarpium) are decocted in water. This rapidly resolves excess heat in Taiyin. Guizhi Jiabaishao Tang (Cinnamon Twig plus White Peony Decoction) removes Gancao (Glycyrrhizae Radix et Rhizoma) and adds Shengjiang (Zingiberis Rhizoma Recens) and Dazao (Jujubae Fructus). It is indicated for Taiyin abdominal pain caused by premature purgation when the exterior syndrome has not yet resolved.