[Meridian Diseases] In Shaoyang diseases, if three days have passed since the onset of cold damage and the Shaoyang pulse has become smaller, it indicates that the condition is about to heal (this refers to the transmission of pathogenic factors along the meridians). Three days after the onset of cold damage, the pathogens in the three Yang meridians should be exhausted, and the three Yin meridians should be affected; however, if the patient can eat and does not vomit, this indicates that the three Yin meridians are not affected by the pathogen (this refers to the transmission of pathogenic factors along the meridians).

[Primary Disease] The typical symptoms of Shaoyang disease include bitter taste in the mouth, dry throat, and dizziness. Five or six days after the onset of cold damage or wind strike, symptoms such as alternating chills and fever, oppression and fullness in the chest and hypochondrium, a silent demeanor with loss of appetite, irritability, and a tendency to vomit may occur. Alternatively, there may be mental restlessness without vomiting, thirst, abdominal pain, stuffiness and hardness under the ribs, palpitations in the epigastrium with difficult urination, lack of thirst with slight body heat, or coughing (all these constitute Xiao Chai Hu Tang syndrome). Due to weak blood and qi, exhaustion of healthy qi, and opening of the interstices, pathogenic factors enter and contend with healthy qi, knotting at the hypochondrium. This contention causes alternating chills and fever occurring at intervals, a silent demeanor with loss of appetite. Since the zang-fu organs are connected, pain must radiate downward; the pathogen is high while the pain is low, thus causing vomiting (all these constitute Xiao Chai Hu Tang syndrome). In cold damage or wind strike, if any symptom of Chai Hu syndrome appears, even just one, it is not necessary for all symptoms to be present (all these constitute Xiao Chai Hu Tang syndrome). Four or five days after the onset of cold damage, symptoms such as body heat, aversion to cold, stiffness and pain in the head and nape, fullness in the hypochondrium, warm hands and feet, and thirst may occur (all these constitute Xiao Chai Hu Tang syndrome). Vomiting accompanied by fever belongs to Xiao Chai Hu Tang syndrome. Six or seven days after the onset of cold damage, with slight fever and aversion to cold, vexatious pain in the joints, slight vomiting, and support-like fullness in the epigastrium, while exterior symptoms persist, this constitutes Chai Hu Gui Zhi Tang syndrome. If ten days have passed since the onset of Taiyang disease, and the pulse is floating and fine with a desire to sleep, the exterior has resolved. If chest fullness and abdominal pain occur, administer Xiao Chai Hu Tang; if the pulse is only floating, administer Ma Huang Tang (these involve Xiao Chai Hu Tang syndrome). In cold damage, if the yang pulse is choppy and the yin pulse is string-taut, abdominal urgency and pain are indicated; first administer Xiao Jian Zhong Tang, and if it does not improve, then administer Xiao Chai Hu Tang (these involve Xiao Chai Hu Tang syndrome). Patients prone to vomiting should not be given Jian Zhong Tang because of its sweet nature (these involve Xiao Chai Hu Tang syndrome). When a woman suffers from wind strike with fever and aversion to cold, and her menses arrive, and after seven or eight days the heat subsides but the pulse becomes slow and the body cool, with fullness in the chest and hypochondrium resembling chest binding and delirium, this is Heat Entering the Blood Chamber. One should puncture Qi Men to drain the heat according to its location (this constitutes Heat Entering the Blood Chamber syndrome). If a woman suffers from wind strike for seven or eight days and subsequently develops alternating chills and fever occurring at intervals, with her menses having just stopped, this is Heat Entering the Blood Chamber. The blood must be knotted, causing symptoms like malaria occurring at intervals; primarily treat with Xiao Chai Hu Tang (this constitutes Heat Entering the Blood Chamber syndrome). If a woman suffers from cold damage with fever, and her menses arrive, she is clear during the day but delirious at night, seeing ghosts, this is Heat Entering the Blood Chamber. Do not violate the stomach qi or the upper two jiaos, and the condition will resolve (this constitutes Heat Entering the Blood Chamber syndrome).

[Transition to Yangming Disease] If thirst occurs after taking Chai Hu Tang, it belongs to Yangming disease; treat according to Yangming methods (belongs to Yangming syndrome). In combined Taiyang and Shaoyang disease with spontaneous diarrhea, administer Huang Qin Tang; if vomiting occurs, administer Huang Qin Jia Ban Xia Sheng Jiang Tang (this represents the pathway from Shaoyang transitioning to Yangming, associated with Da Chai Hu Tang indications). In cold damage with fever, sweating, and unresolved illness, with stuffiness and hardness in the heart, vomiting, and diarrhea (this constitutes Da Chai Hu Tang syndrome, representing the pathway to Yangming). Five or six days into cold damage, with sweating on the head, slight aversion to cold, cold hands and feet, fullness in the epigastrium, unwillingness to eat, hard stool, and a fine pulse, this is Yang Wei Jie (slight Yang knotting), involving both exterior and interior conditions. A deep pulse also indicates an interior condition. Sweating indicates Yang Wei Jie; if it were pure Yin knotting, there would be no exterior symptoms, and all symptoms would be interior. This is half-exterior and half-interior. Although the pulse is deep and tight, it cannot be diagnosed as Shaoyin disease because Yin patterns do not typically present with sweating; the presence of head sweating indicates it is not Shaoyin. Xiao Chai Hu Tang may be administered. If the patient remains uncomfortable, passing stool will resolve the condition (all these constitute Da Chai Hu Tang syndrome, representing the pathway to Yangming). After more than ten days of Taiyang disease, if there is a warm sensation in the heart with a desire to vomit, chest pain, loose stools instead of constipation, slight abdominal fullness, and mild vexation, if the patient had undergone extreme emesis or purgation at that time, administer Tiao Wei Cheng Qi Tang; otherwise, do not administer it. If there is only a desire to vomit, chest pain, and loose stools, this is not Chai Hu syndrome but rather caused by extreme emesis and purgation (all these constitute Tiao Wei Cheng Qi Tang syndrome, representing the pathway to Yangming).

[Transition to Sanyin Disease] Six or seven days into cold damage, without significant heat, if the patient is restless and irritable, this indicates the departure of Yang and entry of pathogens into the three Yin meridians (this is the pathway of transmission into Sanyin).

[Complicated Disease] Originally Taiyang disease transitioning to Shaoyang, presenting with hardness and fullness in the hypochondrium, dry retching, inability to eat, and alternating chills and fever, before emesis or purgation, with a deep and tight pulse, administer Xiao Chai Hu Tang. If emesis, purgation, sweating, or warm needle therapy have already been used, leading to delirium and the cessation of Chai Hu syndrome, this is a Complicated Disease. In cold damage, if the pulse is string-taut and fine with headache and fever, it belongs to Shaoyang. Shaoyang disease should not be treated with sweating; sweating leads to delirium, indicating involvement of the Stomach. If the Stomach harmonizes, the patient recovers; if not, vexation and palpitations occur (this constitutes Delirium and Vexation/Palpitations syndrome, representing the pathway to Yangming). Two or three days into cold damage, with vexation and palpitations (constitutes Xiao Jian Zhong Tang syndrome). In cold damage, if the pulse is knotted and intermittent with palpitations (constitutes Zhi Gan Cao Tang syndrome). In Shaoyang wind strike, with hearing loss, red eyes, chest fullness, and vexation, do not use emesis or purgation; doing so leads to palpitations and fright (this constitutes Vexation/Fullness/Fright/Palpitations syndrome). Eight or nine days into cold damage, if purgation was mistakenly used, resulting in chest fullness, vexation and fright, difficult urination, delirium, heaviness of the entire body, and inability to turn over (constitutes Chai Hu Jia Long Gu Mu Li Tang syndrome). If Chai Hu syndrome was mistakenly purged, but Chai Hu syndrome persists, administer Chai Hu Tang again; the patient will experience shivering followed by fever and sweating, resolving the condition (constitutes Xiao Chai Hu Tang syndrome). If ten days have passed since Taiyang disease, and multiple purgations were performed, but Chai Hu syndrome persists four or five days later, first administer Xiao Chai Hu Tang. If vomiting continues, urgency in the epigastrium, and mild vexation persist, indicating the disease is unresolved, administer Da Chai Hu Tang; purging will resolve it (constitutes Da Chai Hu Tang syndrome). Thirteen days into cold damage, unresolved, with chest and hypochondrial fullness and vomiting, tidal fever in the late afternoon, followed by slight diarrhea: originally a Chai Hu syndrome, but purgation was mistakenly used, which should not cause diarrhea. The current diarrhea indicates the physician mistakenly used pill-based purgatives, which is incorrect treatment. Tidal fever indicates excess; first use Xiao Chai Hu Tang to resolve the exterior, then treat with Chai Hu Jia Mang Xiao Tang (constitutes Da Chai Hu Tang syndrome). Five or six days into cold damage, after sweating and subsequent purgation, with slight knotting in the chest and hypochondrium, difficult urination, thirst without vomiting, only head sweating, alternating chills and fever, and vexation, the disease is unresolved (constitutes Chai Hu Gui Zhi Gan Jiang Tang syndrome, representing the pathway to Taiyin). Six or seven days after onset, with a slow, floating, and weak pulse, aversion to wind and cold, and warm hands and feet, if the physician mistakenly purged two or three times, leading to inability to eat, fullness and pain in the hypochondrium, yellow complexion, eyes, and body, stiffness in the head and nape, and difficult urination, administering Chai Hu Tang will likely result in a feeling of heaviness in the rectum afterward. If the patient is thirsty and vomiting upon drinking water, Chai Hu Tang is contraindicated; eating food may cause hiccups (this constitutes Mis-purging leading to Yellow Body syndrome). In combined Taiyang and Shaoyang disease, with stiffness and pain in the head and nape, or dizziness, sometimes resembling chest binding, and hardness in the epigastrium, puncture Da Zhui, Fei Shu, and Gao Huan acupoints. Do not sweat; sweating leads to delirium. If the pulse is string-taut and delirium persists for five or six days, puncture Qi Men (this constitutes Early Chest Binding syndrome). In combined Taiyang and Shaoyang disease, with hardness in the epigastrium, stiffness in the neck, and dizziness, puncture Da Zhui, Fei Shu, and Gao Huan acupoints. Be cautious against using purgation (this constitutes Early Chest Binding syndrome). Ten or more days into cold damage, with heat knotted in the interior and recurring alternating chills and fever, administer Da Chai Hu Tang. If chest binding exists without significant heat, this is Water Knotting in the Chest and Hypochondrium. With only slight head sweating, Da Xian Xiong Tang is indicated (this constitutes Chest Binding syndrome). Five or six days into cold damage, with vomiting and fever, Chai Hu syndrome is present. If mistakenly purged with other medicines, but Chai Hu syndrome persists, administer Chai Hu Tang again. Although purged, it is not adverse; the patient will shiver, develop fever, and sweat to resolve. If the epigastrium is full and painfully hard, this is Chest Binding, treated with Da Xian Xiong Tang. If full but not painful, this is Pi (Glomus), Chai Hu Tang is contraindicated; Ban Xia Xie Xin Tang is appropriate (this constitutes Chest Binding and Pi syndrome). In combined Taiyang and Shaoyang disease, mistaken purgation leads to Chest Binding, hardness in the epigastrium, continuous diarrhea, inability to take fluids, and mental vexation (this constitutes Chest Binding syndrome). The optimal time for Shaoyang disease to resolve is from Yin hour to Chen hour.

[Formulas]
Xiao Chai Hu Tang: Chai Hu, Huang Qin, Ban Xia, Ren Shen, Gan Cao, Sheng Jiang, Da Zao.
Chai Hu Gui Zhi Tang: Chai Hu, Huang Qin, Ren Shen, Ban Xia, Da Zao, Sheng Jiang, Gui Zhi, Shao Yao.
Xiao Jian Zhong Tang: Gui Zhi, Shao Yao, Gan Cao, Da Zao, Sheng Jiang, Yi Tang.
Huang Qin Tang: Huang Qin, Shao Yao, Gan Cao, Da Zao.
Huang Qin Jia Ban Xia Sheng Jiang Tang: Huang Qin, Shao Yao, Gan Cao, Da Zao, Ban Xia, Sheng Jiang.
Da Chai Hu Tang: Chai Hu, Huang Qin, Shao Yao, Ban Xia, Sheng Jiang, Da Zao, Zhi Shi, Da Huang.
Zhi Gan Cao Tang: Gan Cao, Ren Shen, Da Zao, Sheng Di Huang, E Jiao, Mai Dong, Ma Ren, Gui Zhi, Sheng Jiang.
Chai Hu Jia Long Gu Mu Li Tang: Chai Hu, Ban Xia, Ren Shen, Da Zao, Sheng Jiang, Gui Zhi, Fu Ling, Da Huang, Qian Dan, Long Gu, Mu Li.
Chai Hu Jia Mang Xiao Tang: Chai Hu, Huang Qin, Ban Xia, Sheng Jiang, Ren Shen, Gan Cao, Da Zao, Mang Xiao.
Chai Hu Gui Zhi Gan Jiang Tang: Chai Hu, Huang Qin, Gan Cao, Gan Jiang, Gui Zhi, Mu Li, Gua Lou Gen.
Ban Xia Xie Xin Tang: Ban Xia, Ren Shen, Da Zao, Gan Jiang, Gan Cao, Huang Qin, Huang Lian.