Note: Zhongshu (Heatstroke) and Zhongre (Heat illness), although named differently, are essentially the same disease. If one is injured by cold in winter and it transforms into a heat illness that manifests in summer, this is a disease that arises from within and reaches the exterior after passing the season, commonly referred to as "late-onset" (Wanfa). This cannot be compared to acute new-onset Zhongshu or Zhongre. Some say: The pulse of newly contracted Zhongshu is deficient (Xu), while the pulse of late-onset fever is excess (Sheng). Treatment methods include clearing heat (Qingre) and releasing the muscle layer (Jieji).

In Taiyang Zhongre (Summerheat-Stroke, also known as Zhongye), the symptoms are sweating, aversion to cold, fever, and thirst. (Cheng Wuji's commentary: Sweating, aversion to cold, and fever without thirst indicate Wind-stroke (Zhongfeng); sweating, aversion to cold, fever with thirst indicate Zhongye. Use Baihu Tang.)

In Taiyang Zhongye (Summerheat-Stroke), the symptoms are fever, aversion to cold, heaviness and pain in the body, with a pulse that is wiry-thin (Xianxi), knotted-empty (Kou), or slow (Chi). After urination, there is a sensation of shivering and piloerection, and coldness in the hands and feet. Slight exertion causes immediate fever, open-mouth breathing, and dryness of the anterior teeth. If sweat-inducing methods are misused, aversion to cold worsens; if warm needle therapy is misused, fever intensifies; if purgative methods are misused, strangury (Lin) worsens. (Cheng Wuji's commentary: Diseases can be in the exterior, in the interior, or involving both. This case involves both. Fever, aversion to cold, heaviness, and pain indicate dampness in the exterior. A wiry-thin, knotted-empty, or slow pulse indicates deficiency in Summerheat-pulse. Shivering and cold extremities after urination indicate insufficiency of Taiyang channel Qi. Exertion causing immediate fever implies that labor disturbs Yang, leading to manifestation due to Yang deficiency. Open mouth and dry anterior teeth indicate severe internal heat. The *Neijing* states: "Affected by Summerheat, sweating occurs; when annoyed, panting and drinking follow." Opening the mouth signifies panting and drinking. Due to incessant panting, the anterior teeth become dry. Sweating to remove exterior pathogens damages external Yang, worsening aversion to cold. Warm needles assisting Yang cause internal attack by fire, intensifying fever. Purgatives removing interior heat damage internal fluids, drying the bladder, worsening strangury. ○ Mr. Xu says: This clause lacks treatment methods. Dongyuan used Qingshu Yiqi Tang as the main prescription, which can be said to have revealed a secret of millennia.)

Taiyang Zhongshi (Dampness injury), characterized by fever, painful heaviness, and a weak pulse, results from water-dampness injuring the body in summer, with water qi circulating in the skin. (Cheng Wuji's commentary: The *Neijing* states: "Deficient pulse and fever result from Summerheat injury." Fever with a weak pulse indicates Summerheat; painful heaviness indicates water-dampness. In summer, when heat prevails, watering the body leads to this disease. ○ Guadi Yiwu San may be used, or some say Wuling San.)

Zhongshi resembles Shanghan but differs.

Mr. Zhang says: Clear pathogens (such as wind and summerheat) affect the upper part, while turbid pathogens (such as cold and dampness) affect the lower part. Wind, cold, and dampness belong to earth qi and are considered turbid, thus affecting the foot meridians. Only Summerheat belongs to heaven qi and is considered clear, thus affecting the Hand Shaoyin Heart Meridian. Its symptoms often resemble Shanghan, but the pulse differs. Although Shanghan presents with aversion to cold and fever, initial stages do not reach annoyance and thirst. Summerheat, however, presents with thirst from the onset, distinguishing it from Shanghan. Furthermore, the Shanghan pulse must be floating and excess (Sheng), whereas the Summerheat pulse must be deficient (Xu), sometimes wiry-thin, knotted-empty, or slow. The *Neijing* states: "Excess pulse with cold body results from Shanghan; deficient pulse with fever results from Summerheat injury." This refers to the above. For instance, Taiyang disease presenting with stiffness of the neck and back, accompanied by sweating and aversion to wind, might resemble Zhongshi during hot summer months. However, since there is no thirst, Guizhi Jia Gegen Tang is used. During summer and autumn, in times of intense heat, one must carefully examine according to the classics to avoid errors.

Mr. Wang says: From the perspective of symptoms, Shanghan involves aversion to cold, while Shangre (Summerheat) involves aversion to heat. From the perspective of pulse, Shanghan has an excess pulse, while Summerheat has a deficient pulse. Moreover, the deficient and thin pulse of Summerheat resembles that of Dampness and Jing (Spasm), but the symptoms differ: Summerheat involves spontaneous sweating and thirst, Dampness involves no thirst, and Jing involves body pain.

A洪 (Hong) pulse, fever, and aversion to cold indicate Rebing (Heat Disease).

The *Huoren* book states: In summer, fever, aversion to cold, headache, heavy body and limb pain, with a洪 (Hong) and full pulse, indicate Heat Disease. This is cold injured in winter, manifesting as Heat Disease due to summer heat. Treating Heat Disease is similar to Shanghan: use Guizhi Tang if sweating; Mahuang Tang if no sweating. If irritability exists, Da Qinglong Tang is suitable. However, summer medications should have a cooling nature and not be too warm. Guizhi Tang, Mahuang Tang, and Da Qinglong Tang require modifications. Before the Summer Solstice, add half liang of Huangqin to Guizhi Tang. After the Summer Solstice, add one liang of Zhimu and two liang of Shigao to Guizhi, Mahuang, or Da Qinglong Tang, or add half liang of Shengma. Generally, Guizhi and Mahuang Tangs are warm in nature. In warmer regions, unlike the northwest, using them in summer inevitably leads to jaundice and macules. If Heat Disease persists beyond three days despite these decoctions, with a still rapid pulse indicating pathogenic factors remaining in the channels and not entering the zang-fu organs, Guizhi Shigao Tang is used. This formula replaces Guizhi indications after the Summer Solstice. Adding one liang of Mahuang allows it to replace Mahuang Qinglong indications. For late-onset Shanghan from March to summer, Zhizi Shengma Tang is also可选 (selectable). (In the Gui Mao year of Wanli, the son-in-law of Mr. Li from Xinghua went to Nanjing for exams. It was midsummer, and he contracted Shanghan. This Taixue student had just read Zhang Zhongjing's works, boasted of his medical knowledge, and administered Guizhi Tang, resulting in immediate death. Generally, Mahuang and Guizhi are medicines for severe Shanghan in deep winter. Using them on Warm Diseases is inadvisable, let alone Heat Diseases.)

Guizhi Shigao Tang: See previous discussion for treatment principles. Sweating with a slow pulse indicates Guizhi syndrome; no sweating with a tight pulse indicates Mahuang/Qinglong syndrome.
Ingredients: Guizhi (remove bark), Huangqin (each half liang), Zhizi (3 qian), Baishao Yao, Shengma, Gange, Shengjiang (each 7.5 qian), Shigao (crushed), Gancao (roasted, each 1 liang). Crush the herbs. Take 5.5 qian per dose, boil in 1.5 cups of water until 0.8 cup remains, strain, and take after a meal interval. Stop subsequent doses upon sweating.

Zhizi Shengma Tang: Treats late-onset Shanghan, occurring from March to summer.
Ingredients: Shengdihuang (chopped, half jin), Zhizi (10 pods, split), Shengma (1.5 liang), Chaihu, Shigao (each 2.5 liang). Crush the herbs. Take 5 qian per dose, boil in 1.5 cups of water until 0.8 cup remains, take in one dose. If the illness does not resolve, administer again.

Mr. Wu says: After the Summer Solstice, during hot weather, someone may present with high fever, severe thirst, and aversion to cold absent. This is Heat Disease. A floating and洪 (Hong) pulse indicates involvement of the Taiyang channel; a洪 and long pulse indicates Yangming; a wiry and rapid pulse indicates Shaoyang. These three Yang channels are treatable. However, a sinking, fine, small pulse with cold feet indicates involvement of the Three Yin channels, which is difficult to treat. Generally, for severe Heat Disease, a洪大 (Hongda) or slippery-rapid forceful pulse indicates correspondence between pulse and disease, making it treatable. A small, weak, or forceless pulse is difficult to treat. If the patient is deficient with a weak pulse, Ren Shen Tang should be given to support Yuanqi (Primal Qi). Do not attack the heat. If the pulse is洪, body hurts, high fever, no sweating, and irritability exist, Liushen Tang should be used to induce sweating. Alternatively, Renshen Qianghuo San plus Gegen, Douchi, and Shengjiang can induce sweating. Mild cases may use Shiwei Xiong Su San. If complicated by Summerheat, add Xiangru and Bian Dou for dual resolution. If complicated by internal injury from cold/raw food stagnation, vomiting, nausea, epigastric fullness, aversion to wind, or chills/stiffness, Huoxiang Zhengqi San plus Xiangru, Bian Dou, and Gegen induces sweating, named Erxiang Tang. If sweating fails to resolve the heat: in Taiyang, use Renshen Qianghuo San plus Huangqin; in Yangming, use Shengma Gegen Tang plus Huangqin; for severe heat, dryness, thirst, and large pulse, use Baihu Tang plus Ren Shen; in Shaoyang, use Xiaochaihu Tang with modifications. If complicated by Summerheat, add Huanglian and Xiangru. If heat with spontaneous diarrhea, difficulty urinating, and thirst exist, use Wuling San minus Guizhi plus Gegen, Huanglian, Xiangru, and Huashi. If exterior and interior heat coexist with spontaneous diarrhea, floating-rapid pulse, and difficulty urinating, use Xiaochaihu Tang combined with Siling San. If unresolved, or if transmission/complications occur, such as interior excess requiring purgation, interior cold requiring warming, or macules/jaundice, treat according to standard Shanghan protocols. Generally, Heat Disease with diarrhea, abdominal fullness, and severe heat on day 1-2 is fatal; drowsiness, delirium, severe heat with small pulse on day 3-4 is fatal; severe heat, small pulse, cold feet on day 4-5 is fatal; no sweating, vomiting, delirium, coma, rapid pulse on day 5-6 is fatal; blackened/dry tongue root on day 6-7 is fatal; nosebleed/vomiting blood, dry heat, large pulse on day 7-8 is fatal; spasms, convulsions, confusion on day 9 is fatal. Any Heat Disease with Cu, Jie, Dai, sinking, or small pulses is difficult to treat. Heat Disease without sweating and with a restless pulse is fatal; sweating followed by intensified heat and restless pulse is fatal.

Deficient pulse, fever, and aversion to cold indicate Zhongshu (Summerheat Stroke).
Treatment methods and formulas are detailed in the Miscellaneous Diseases section and subsequent clauses.

Cold calves, abdominal fullness, headache, thirst without fever indicate Shiwen (Damp-Warmth).

The *Huoren* book states: Shiwen presents with cold calves, chest/abdominal fullness, excessive sweating, headache, and delirious speech. The person is often injured by dampness and then contracts Summerheat; dampness and heat combine to cause Shiwen. The pulse is ru (soft) and weak in the yang position, and small and urgent in the yin position. Treatment targets the Taiyang channel; sweating is contraindicated. If sweated, the patient will lose voice, become deaf, unaware of pain location, with blue skin and changed complexion, called Zhongyi (Heavy Stroke). Such deaths are caused by the physician. Use Baihu Jia Cangzhu Tang.

Scholar Xu says: In the Gui Chou year, my old friend Wang Yanlong served as Cangguan in Piling. In late summer, he fell ill with excessive sweating in the chest and neck, cold calves, and delirium. Physicians did not understand and administered mixed drugs for ten days. I diagnosed his pulse as ru at the guan front and shu (rapid) at the guan rear. I stated it should be treated as Shiwen. Having first contracted Summerheat and then dampness, the combination is named Shiwen. First use Baihu Jia Renshen Tang, then Baihu Jia Cangzhu Tang. Headache receded, feet warmed, sweating stopped, cured in three days. This is called Zei Xie (Thief Pathogen). Someone asked: What is Thief Pathogen? I said: The *Nanjing* mentions five pathogens: Shi, Xu, Zheng, Wei, and Zei. Coming from behind is Xu; coming from ahead is Shi; coming from the unconquered is Zei; coming from the conquered is Wei; self-caused is Zheng. Also: Assuming heart disease, Summerheat is Zheng; contracting dampness is Zei. Now, the heart first suffered Summerheat, and dampness prevailed. Water overcomes Fire, coming from the unconquered, hence called Zei Pathogen. Among the five, it is the most adverse. The *Nanjing* states: Shiwen pulse is ru and weak in yang, small and urgent in yin. Ru and weak in yang indicates dampness combining with Summerheat; small and urgent in yin indicates Summerheat steaming dampness. Thus, the scripture says: Summerheat and dampness combine, named Shiwen, which is called Zei Pathogen. Not only this, I have had retained fluid pathology. Every summer, my calves sweat and never dry. Taking this medicine two or three cups cures me.

Haizang says: For Shiwen with little sweating, use Baihu Jia Cangzhu Tang; for profuse sweating, use Baihu Jia Guizhi Tang (Formula see above).

Sun Taizhen says: Outside Baoqing Gate, there was a wine merchant surnamed Jiang who sang well. Sun loved him. He disappeared for several days. Inquiry revealed he was dying of illness. Sun diagnosed him: body moist, cold calves down to knees, abdominal fullness, unconsciousness, six pulses small, weak, and urgent. Asked about taken medicines, they were all yin-disease medicines. Sun said: This is not severe disease, but medicine aggravating the condition. Used Wuling San and Baihu Tang for over ten doses. Condition improved slightly, cured after further doses. Jiang thanked Sun and asked for the method. Sun said: Your disease is Summerheat injury. Initially, Yang was weak and厥 (Jue) with small, forceless pulse. Doctors thought it was yin disease and used yin medicines, worsening the Jue. I used Wuling San to strongly promote urination, reducing abdominal fullness; Baihu Tang cleared pathogenic heat, curing the disease. In yin diseases, calves and arms are both cold. You have cold calves but warm arms, indicating it is not lower Jue ascending upper, thus knowing it is Yang weak Jue.

Bao says: Between Lixia (Start of Summer) and Chushu (End of Heat), Shanghan patients often have slight coolness, spontaneous sweating, and heavy limbs, called Shiwen. Cangzhu Shigao Tang is used (i.e., Baihu Jia Cangzhu Tang).
Cangzhu Shigao Tang Formula: Cangzhu (half liang), Shigao (3 qian), Zhimu (2.5 qian), Gancao (1 qian). Crush, boil in one cup water until half cup remains, take warm. Indicates internal dampness; usually no desire to drink. If fever,洪 pulse, no sweating, and excessive thirst exist, heat accumulates in the upper jiao/chest. Use Jiegeng San (This is not Shiwen, but Heat Disease).
Jiegeng San Formula: Bohe, Huangqin, Gancao, Zhizi (each 1 qian), Lianqiao (2 qian), Jiegeng (3 qian). Cut, take 5 qian per dose, boil in water, add Zhuye. If stool is constipated, add Dahuang half liang.

Deficient pulse, fever, resulting from Summerheat injury.

Liu Chun says: According to Scholar Xu, Summerheat injury presents with wiry-thin, knotted-empty, or slow pulses. The *Neijing* states: "Cold injures form, heat injures Qi." Injuring Qi without injuring form leads to Qi consumption and deficient pulse. Wiry-thin, knotted-empty, and slow are all deficient pulses. Zhongjing considers wiry as yin, and Zhu Gong also states Summerheat pulse is fine and weak, confirming they are deficient pulses.

Summerheat syndromes include Mao (Covering), Shang (Injury), and Zhong (Stroke).

Mr. Dai says: Differences in severity among Mao, Shang, and Zhong. Abdominal pain, watery diarrhea, stomach/intestine involvement, nausea due to phlegm-fluid in the stomach opening are Mao Shu (Covering Summerheat). Use Huanglian Xiangru Yin (Huanglian clears heat, Xiangru dispels summerheat). Fever, headache, restlessness, or sensation like needle pricks in the body indicate Re Shang Roufen (Heat injuring flesh/muscle). Use Jiedu Baihu Tang plus Chaihu; add Ren Shen for Qi deficiency. Cough, alternating chills/fever, night sweats, rapid pulse indicate heat injuring Lung meridian, fire attacking metal. This is Zhong Shu (Stroke Summerheat). Use Qingfei Tang, Chaihu Tianshui San, etc.

Summer months: Hidden Yin inside.

Danxi says: In summer, Yang qi emerges fully to the surface. The abdomen, belonging to earth qi, becomes empty as qi floats to the skin surface. Thus, "Hidden Yin inside" in summer means Yin refers to emptiness/deficiency. Viewing it as cold/yin-cold is erroneous. Predecessors used Dashun San (warm/hot drugs) for Summerheat, likely for injuries from cool pavilions, water towers, springs, or ice/snow, not for "Hidden Yin." During fire commands, stones melt and metals flow; where is the cold/yin? Sun Taizhen recommended Shengmai San in summer, implying deficiency. Liu says: Jiegu states: Quietly acquired is Zhongshu; actively acquired is Zhongre. Dongyuan states: Acquired in deep halls/palaces avoiding heat is Zhongshu, suitable for Dashun San; acquired through labor is Zhongre, suitable for Cangzhu Baihu Tang. Summerheat and heat are one, the qi of summer. Why distinguish Zhongshu from Zhongre if illness comes from staying in cool halls? Mr. Wang says: Summerheat is the command of summer. Fire moves between heaven and earth. Labor or hunger depletes Yuanqi, insufficient to resist extreme heavenly conditions, leading to injury named Zhongshu or Zhongre, essentially the same. Why divide by movement/rest? Zhongshu mostly affects laborers; labor causes deficiency, allowing pathogen entry. If not deficient, even extreme conditions cannot harm. Those avoiding heat in deep halls getting headache, aversion to heat, etc., resemble Shanghan, not Zhongshu. Their annoyance and skin heat are not Summerheat pathogens but Yang qi obstructed by yin-cold. Since not Summerheat, why call it Zhongshu? To treat, use acrid-warm light-floating agents to disperse. Dashun San contains mostly Gancao, followed by Ganjiang, Xingren, Rougui. Except Rougui, others are roasted. Originally intended for patients with hidden heat drinking excessively, spleen/stomach dampness, vomiting undigested food, organ dysfunction. Gancao and Ganjiang are fire-roasted; Rougui (not Guizhi) is a warm middle-jiao drug. Xingren is for descending Qi. Using this for quietly acquired cases may fail to release the exterior and increase internal annoyance. Modern people mistakenly think Yin qi in summer is cold, insisting on Dashun San. Yin qi is not cold qi; summer Yang disperses outward, Yin stays inward. Is Yin cold? Why drink water in summer? Cangzhu Baihu Tang is suitable but not a universal remedy. Must refer to various Summerheat formulas and use based on symptoms to be reasonable. Quietly acquired cases, though in summer, are not Summerheat diseases; distinguish them to avoid future confusion.

Summerheat injuring Five Zang organs presents differently.

Mr. Chen says: Summerheat entering Heart causes choking, fullness, coma; entering Liver causes dizziness, numbness/paralysis; entering Spleen causes drowsiness/unawareness; entering Lung causes cough/fullness, flaccidity; entering Kidney causes wasting-thirst. Mr. Xu says: Summerheat symptoms vary greatly, not limited to Five Zang. Human constitution varies in deficiency/excess, infection in severity. Mild cases manifest later, becoming malaria/dysentery in early autumn; severe cases manifest immediately, as listed above. Severity can change. Infection depth and transmission complications vary. Human physical/mental states differ, so variations occur. This applies to all seasons.

Summerheat diseases benefit from tonifying Yuanqi.

Dongyuan says: With weak Spleen/Stomach, encountering dampness in July/August, sweating, heavy body, shortness of breath, flaccid limbs, drooping eyes, indicates exhaustion of Kidney and Bladder. Profuse sweating loses Jin Ye (Body Fluids), governed by Geng Large Intestine. In Sanfu, Geng Metal is imprisoned, Wood uncontrollable, so Wind-Damp combines, causing joint pain. Ren Bladder ends at Si, Gui Kidney Water ends at Wu. Now meeting dampness aiding heat as pathogen, northwest cold/clearness is exhausted. Sage legislation: Summer requires tonification because heat injures Yuanqi. Use Ren Shen, Maidong, Wuweizi to nourish Water source, drain internal fire, tonify Geng Metal, benefit Yuanqi.

Summerheat stroke causing Flaccidity/Jue syndromes.

Dongyuan says: Long Summer damp-heat steams humans, damaging Yuanqi. Limbs tired, spirit low, legs flaccid. Cold Jue occurs morning/evening; heat like fire occurs midday. Both Yin/Yang and Qi/Blood are deficient. Chest/epigastric fullness, limb heaviness/pain, high Qi/panting, fever/annoyance, yellow/scanty urine, loose/frequent stool or diarrhea/thirst, spontaneous sweating, heavy body indicate Blood diseased first, Qi unaffected. If Dampness attacks first, pulse is洪缓 (Hong-huan) and slow. Illness may improve slightly, but heavenly damp-heat command remains. Use drying-clearing agents. Walking far in great heat/thirst places heat in Kidney, Water cannot overcome Fire, causing Bone Flaccidity (Hot-Damp Flaccidity). Hot Jue due to Yin deficiency; Cold Jue due to Qi deficiency. Limbs like fire = Hot Jue; cold limbs = Cold Jue. Cold Jue has cold in abdomen; Hot Jue has heat in abdomen, as Spleen governs limbs. Mr. Xu says: This discusses Summerheat symptoms similarly to Winter Shanghan transmission variations. Cold injures Form; Heat injures Qi. If Yuanqi is very deficient, sudden illness unrescued is same as Shanghan Yin Du killing instantly. Dongyuan opened this case study, enlightening later generations' blindness. Compare with Flaccidity chapter.

Summerwind (Shufeng).

Mr. Jia says: Caused by Fire controlling Metal, failing to calm Wood. Convulsions, unconsciousness. Floating-deficient pulse indicates Wind; Deficient indicates Summerheat. Commonly named Summerwind, it is Minister Fire prevailing. First dissolve Suhexiang Wan in warm water, then Huanglian Xiangru Yin plus Qianghuo, or Shuangjie San plus Xiangru is excellent.

General Principles of Treating Summerheat.

Mr. Jia says: Summerheat is Minister Fire commanding. Affected persons have deficient pulse. Exterior symptoms: headache, dry mouth, greasy face, sweating, fatigue, or aversion to back heat. Severe cases: confusion, unconsciousness, cholera-like vomiting/diarrhea, phlegm obstruction, retching, abdominal pain, bloody diarrhea, jaundice, macules. Treatment prioritizes clearing Heart and promoting urination. For profuse sweating, do not promote urination; use Baihu Tang. Then differentiate exterior/interior. Exterior: headache/aversion to cold, use Shuangjie plus Xiangru, Erxiang San, Shiwei Xiangru San. Half-exterior/half-interior: diarrhea/thirst/vomiting, use Wuling San. Severe heat/thirst, use Yiyuan San. Exterior resolved, interior heat: Banxia Jiedu Tang + Shenxiong Wan. Elderly/weak people affected by Summerheat, faint pulse, diarrhea, thirst preferring warmth, or cold Jue/unconsciousness: Zhuyeshigao Tang plus Shu Fu half piece, frozen drinks, then Laifu Dan, Wuling San. Summer Summerheat must not use hot/dry agents causing macules, jaundice, urinary difficulty, confusion, and death. Mr. Xu says: This covers Summerheat treatment thoroughly. However, using Suhexiang Wan for Summerwind/Minister Fire, and Shuangjie, requires careful pulse/symptom examination. Suhexiang Wan is for Yin-Cold obstruction, internal cold/raw food injury, Qi blockage, or Evil Strike, not Summerwind/Minister Fire. Scholars must note this. Mr. Tao says: Summerheat pulse is deficient and hidden. Fever, back aversion to cold, greasy face, sweating, irritability, great thirst, piloerection, aversion to cold, coma, fatigue, no body pain. Differs from Shanghan. Internal/external heat, dry mouth/thirst, slight cold limbs, no body pain: use Baihu Tang. Phlegm/retching/aversion to cold: Jupi Tang. Heat oppression/no aversion to cold: Zhuyeshigao Tang. Headache/nausea/irritability/epigastric discomfort/urinary difficulty: Wuling San. Xia Xiao Shu Wan. Summerheat use Xiaochaihu Tang (best).