暑有阴阳二症。阳症因于中热，阴症因于中寒，但感在夏至后者，皆为之暑耳。时令大寒、小寒而
人受之者，为伤寒。时令大暑小暑而人受之者，为伤暑。经云∶伤暑者汗，烦则喘喝，静则多言。
此皆中暑之阳症。即洁古所谓动而得之为外感。天日之暑热，故为汗出烦躁、为喘、为大声呼
喝，即其静者，亦不免于多言。盖邪热伤阴，精神内乱，故言语无伦也。又曰∶体若燔炭，汗出而散。
此言中暑之阴症，即洁古所谓静而得之。因避天之暑热，而反受阴寒所致。故体热若燔炭，必须汗出
邪乃得散。经言∶暑当与汗皆出勿止。此之谓也。但感而即病、则伤寒也，若不即病、至秋而发，则如经
所谓夏伤于暑，秋必 疟。又谓∶夏暑汗不出者，秋成风疟皆由此耳。观经言二症；一中于热，一
中于寒，皆谓之暑。但治寒宜散，必汗出而解。治热宜凉，必热清而愈。不可不察也。
白虎加人参汤 《金匮》云∶太阳中热者、 〔同暑〕是也。
〔此言暑之阳症。盖太阳膀胱，乃六经之首，主皮肤、而统荣卫。故凡六淫之邪，必由太阳而入。〕
汗出恶寒，〔暑伤心气，心虚则汗出，暑伤肺气，肺虚则恶寒。亦有不恶寒，反恶热者。〕身热而渴，〔表
有暑邪则热，里有暑邪则渴。亦有身不热者。〕六脉虚弱，〔暑伤于气，所以脉虚。〕此方主之。
人参〔补元气，〕石膏〔清暑邪，〕知母〔清肺热。〕甘草〔解暑和中。〕粳米〔
养胃气。〕仲淳加麦冬〔救肺金，存津液，以夏月之热淫，必僭而犯上，伤其肺金也。〕竹叶〔清心
涤热。〕脉不甚虚者，可去人参。兼有湿热者，合益元散，或加茅术。
此方凉肺清心，养胃生津，但用甘寒阴阳两无偏胜之药，清解暑热，而平治之。盖夏月人身之
阳，以汗而外泄，人身之阴，以热而内耗，阴阳俱不足，故仲景于中暑病，禁用汗、下、温针。恐汗
则伤其阳，下则伤其阴，温针则引火热内攻也。按经云∶身热脉虚得之伤暑。盖热伤气，而不伤形，所
以脉虚。故清暑益气，兼而行之。须知暑热之病，有三、四部无脉者，被火所逼而藏伏耳。甚至体痛、烦心，
或喘促、厥冷，若误认虚寒、而投温补，必毙。但用前方，俾暑邪清而脉自起，症自平矣。凡夏月日中
劳役，触冒暑热，而见汗出、烦躁、多言、齿燥、口渴、眩晕者，即属中热的症，此方加减，无不神
效。若国中昏倒，急扶阴凉处，
取土罨病患脐上，小便溺之，盖脐乃命蒂、溺脐以接其元气之意，随灌人溺，〔一碗。〕或用冰水
调益元散。
益元散〔即天水散。〕治中暑、身热、烦渴、小便不利。
滑石〔寒能清热，淡能利窍，六两。〕甘草〔和中，一两。〕为末，每服三、五钱。白汤调
下，冷开水更佳。加薄荷〔少许。〕名鸡苏故。加青黛〔少许。〕名碧玉散。加辰砂〔性微寒，纳浮游
之火，而安神明。凡心热者，非此不能解也。〕名辰砂益元散，治疗并同。
此方驱暑邪从溺而出。以暑热伤心，心与小肠为表里，泄小肠之热，即所以清心也。按嘉言云∶外
暑蒸动内湿，二气交通，因而中暑，所以肥人湿多，中暑最宜。故治中暑病，须知兼治其湿。益元散利
水驱湿，故称夏月服之解暑。然体盛湿多则宜之。清 无湿之人，津液为时令所耗，当用生脉散。若再利
小水，竭其下泉，枯槁立至。凡汗多之体，亦不可利其小便。盖胃中只此津液，汗既外泄，又复下利，
所谓立匮之术也。
生脉散 治热伤元气，肢体倦怠、气短懒言，口干作渴，汗出不止。
人参〔补肺气。〕麦冬〔清肺气，等分。〕五味子〔敛肺气，减半。〕
此方补肺、清肺、敛肺、名生脉者，以脉得气则充，失气则弱，一补、一清、一敛，养气之道毕
矣。凡瘦弱虚人，夏月最宜长服。按东垣云∶夏月加黄 、甘草、服之令人气
力涌出。孙真人云∶夏月必服五味以补五脏之气。寇宗 云∶麦冬、五味、枸杞同为生脉之剂。故
一方用五味、枸杞煎汤代茶，治夏日虚病倦怠、食少、口干、身热者甚宜。
清暑益气汤 治长夏湿热蒸腾，食少倦怠，〔湿热伤脾所致。〕痞胀溏泄，〔脾不运则痞胀，脾
受湿则溏泄。〕体重疼痛，〔湿伤肌肉，故身体重，湿热相搏，故肢节痛。〕身热多汗，〔暑邪干
卫也。〕口渴心烦，小便黄赤，〔暑热伤肺，故口渴，暑热伤心，故心烦，溺赤。〕六脉虚弱。
人参 黄 白术 陈皮 甘草 当归 升麻 干葛〔即补中益气汤，去柴胡而易干葛也。此因
便泻，故以二味鼓舞胃气上行，以治虚泻。〕茅术 黄柏〔即二妙散，合泽泻以治湿热。〕泽泻
青皮 神曲〔下气消食。〕麦冬 五味〔合人参即生脉散也，所以救暑伤之肺。〕
此方补中实卫，以去其湿热。色白内虚之人，夏月无论中暑与否，所宜常服者也。
黄连解毒汤〔见伤寒。〕治夏月一切暑热之症，或合白虎汤，随症加减用之。
此治实火之方也。嘉言谓∶病之繁而且苛者，莫如夏月为最。日之暑气、天之热气、地之湿气、时
分时合。其分也，以风动于中，胜湿解蒸，不觉其苦，其合也，天之热气下，地之湿气上，人在气交
之中，受其炎蒸无隙可避，多有烦躁神昏，肌肤痱起，胸膺痤出，头面疖生，甚则发为肿毒痈疽等
症。或有头面外项赤肿，或咽喉肿痛，或腿足热肿，长至
数寸，不能步履，统宜清凉，解其暑毒，热症一解，赤肿自消，全无脓血。又有遍身发泡，如
桃、李，如碗、如杯，晶莹脆薄，中含臭水，此湿热之水，泛于皮肤也。亦宜本方加减治之。
吞薷饮 治夏月乘凉饮冷，阳气为阴寒所遏，头痛、发热、恶寒、无汗。〔皆乘凉感寒表症，即
经所谓体若燔炭汗出而散也。〕吐泻腹痛。〔此饮冷伤脾胃之故，乃里症也。〕
香薷〔辛温发越阳气。为夏月解表之药。一、二钱。〕
浓朴〔暖脾胃，止腹痛，姜汁炒。一钱。〕扁豆〔补脾胃止吐泻，炒二、三钱。有表症者去
之。〕表症甚者，可加防风、薄荷。如无汗，再加苏叶。〔偏于表者，表药为君。〕里症甚者，可加
陈皮，茯苓、木香、砂仁。〔偏于里者，里药为君。〕如兼心烦溺赤，〔此由暑邪内伏，寒包暑症
也。〕或加黄连，或加益元散。〔清其伏暑。〕虚者加人参。〔即十味香薷饮法。〕
此夏月解表而兼和里之剂。盖纳凉广厦，阳气为阴寒所遏，故有头痛发热，恶寒无汗之症，此在
表而不在里也。过食生冷，则胃家为生冷所伤，故有吐泻腹痛之症，此在里而不在表也。均伤寒冷，表
里悬殊，用药亦异。又嘉言谓∶冒暑之霍乱吐泻，以清暑为主，避暑之霍乱吐泻，以和中、温中为
主；不可不辨。
Summerheat illness is divided into two types: Yin syndrome and Yang syndrome. Yang syndrome arises from contracting heat pathogens, while Yin syndrome arises from contracting cold pathogens. However, any pathogenic contraction occurring after the Summer Solstice is collectively referred to as summerheat illness. When contracted during periods of Major Cold or Minor Cold, it is termed Cold Damage (Shanghan). When contracted during periods of Major Heat or Minor Heat, it is termed Summerheat Damage (Shangshu). The Classics state: "In cases of Summerheat Damage, there is sweating; if vexation occurs, there is panting and loud calling; in a quiet state, there is excessive talking." These are all symptoms of Yang syndrome in summerheat illness. This corresponds to Li Dongyuan's (Jiegu) concept of "obtained through movement," which belongs to external contraction. Due to the scorching heat of the sun and sky, it leads to sweating, vexation, panting, and loud calling. Even when quiet, excessive talking is inevitable. This is because the pathogenic heat damages Yin Qi, causing internal disorder of the spirit, resulting in incoherent speech. It is also stated: "The body feels hot like burning charcoal; only after sweating can the pathogen be dispersed." This refers to Yin syndrome in summerheat illness, corresponding to Li Dongyuan's concept of "obtained through stillness." It is caused by attempting to avoid the heavenly summerheat but instead contracting Yin-cold. Thus, the body becomes hot like burning charcoal, and sweating is required to disperse the pathogen. The Classics say: "Summerheat should be expelled along with sweat; do not stop it." This is what is meant. However, if illness appears immediately upon contraction, it is Cold Damage; if it does not appear immediately but manifests in autumn, it is as the Classics state: "If harmed by summerheat in summer, malaria will occur in autumn." It is also said: "Those who do not sweat during summer heat will develop wind-malaria in autumn," all stemming from this. Observing these two conditions mentioned in the Classics: one involves contracting heat, the other cold, both are called summerheat. However, treating cold requires dispersion, resolving only after sweating; treating heat requires cooling, resolving only after heat clears. This distinction must not be overlooked.
Baihu Jia Renshen Tang (White Tiger Decoction plus Ginseng)
The *Jingui Yaolue* states: "Taiyang Zhongre" (Summerheat affecting the Taiyang channel) is this condition. [This refers to the Yang syndrome of summerheat. The Taiyang Bladder channel is the head of the six channels, governing the skin and commanding Ying and Wei. Therefore, all Six Evils enter via the Taiyang channel.] Symptoms include sweating and aversion to cold (Summerheat damages Heart Qi; Heart deficiency leads to sweating; Summerheat damages Lung Qi; Lung deficiency leads to aversion to cold. There are also cases without aversion to cold, but rather aversion to heat), fever and thirst (Exterior summerheat causes fever; Interior summerheat causes thirst. There are also cases without fever), and weak pulses in all six positions (Summerheat damages Qi, hence the weak pulse). This formula governs these symptoms.
Renshen (Ginseng Radix et Rhizoma) [Tonifies Original Qi], Shigao (Gypsum Fibrosum) [Clears Summerheat Pathogens], Zhimu (Anemarrhenae Rhizoma) [Clears Lung Heat], Gancao (Licorice Root) [Resolves Summerheat and harmonizes the Middle], Jingmi (Oryza Sativa Grain) [Nourishes Stomach Qi]. Chen Zhongchun adds Maidong (Ophiopogonis Radix) [Saves Lung Metal and preserves fluids, as summer heat overflows and attacks upward, damaging Lung Metal], Zhuye (Bambusae Folium) [Clears the Heart and washes away heat]. If the pulse is not significantly weak, Renshen may be omitted. If damp-heat is present, combine with Yiyuan San or add Baizhu (Atractylodis Macrocephalae Rhizoma).
This formula cools the Lungs and clears the Heart, nourishes Stomach Qi and generates fluids. It uses only sweet and cold herbs that neither favor Yin nor Yang excessively, clearing and resolving summerheat to restore balance. In summer, the body's Yang Qi escapes through sweat, and Yin Qi is consumed internally by heat, leading to insufficiency of both Yin and Yang. Therefore, Zhang Zhongjing strictly forbids diaphoresis, purgation, and warm needle therapy for summerheat illness. Diaphoresis would damage Yang; purgation would damage Yin; warm needles would draw fire inward. According to the Classics: "Fever with weak pulse results from Summerheat Damage." Heat damages Qi but not Form, hence the weak pulse. Thus, one must clear summerheat and tonify Qi simultaneously. Note that in summerheat illness, the absence of pulse in three or four positions indicates pathogen suppression by fire. Severe cases may present with body pain, vexation, panting, or cold extremities. Misdiagnosing these as deficiency-cold and administering warming tonics will lead to death. Using the aforementioned formula allows the summerheat pathogen to clear, the pulse to return, and symptoms to subside. For those laboring under the midday sun in summer, exposed to summerheat, presenting with sweating, vexation, excessive talking, dry teeth, thirst, and dizziness, these belong to the heat-struck syndrome. Modifications of this formula are invariably effective. If fainting occurs outdoors, immediately move the patient to a cool, shaded place. Apply mud to the umbilicus and pour urine upon it, as the umbilicus is the root of life force, and pouring urine aims to reconnect Yuan Qi. Immediately administer one bowl of human urine, or mix Yiyuan San with ice water.
Yiyuan San (also known as Tianshui San)
Treats summerheat illness with fever, vexation, thirst, and difficult urination.
Huashi (Talcum) [Cold nature clears heat; bland taste opens orifices, 6 liang], Gancao (Licorice Root) [Harmonizes the Middle, 1 liang]. Grind into powder. Take 3–5 qian per dose, mixed with white boiled water; cold boiled water is better. Add Bohe (Menthae Haplocalycis Herba) [a small amount] to name Jisu San. Add Qingdai (Indigo Naturalis) [a small amount] to name Biyu San. Add Chensha (Cinnabar) [Slightly cold; anchors floating fire and calms the Spirit. Essential for clearing Heart heat] to name Chensha Yiyuan San. Indications remain the same.
This formula expels summerheat pathogens via urination. Since summerheat damages the Heart, and the Heart and Small Intestine are exterior-interior pairs, draining Small Intestine heat clears Heart heat. Zhang Jiebin (Jiayan) states: External summerheat steams internal dampness; the interaction of these two qi leads to summerheat illness. Hence, obese individuals with abundant dampness are most susceptible. Therefore, treating summerheat requires addressing dampness. Yiyuan San promotes urination to drive out dampness, hence its reputation for relieving summerheat in summer. However, it suits those with robust constitutions and excess dampness. For those with clear emptiness and no dampness, whose fluids are depleted by seasonal heat, Shengmai San should be used. Further promoting urination would exhaust the lower source, leading to immediate withering. Those with profuse sweating should also avoid promoting urination. The Stomach contains limited fluids; if they escape via sweat and are further drained downward, it is a recipe for rapid demise.
Shengmai San (Pulse-Generating Powder)
Treats heat damaging Original Qi, manifesting as limb fatigue, shortness of breath and reluctance to speak, dry mouth and thirst, and incessant sweating.
Renshen (Ginseng Radix et Rhizoma) [Tonifies Lung Qi], Maidong (Ophiopogonis Radix) [Clears Lung Qi, equal parts], Wuweizi (Schisandrae Fructus) [Astringes Lung Qi, half dose].
This formula Tonifies, Clears, and Astringes the Lung. It is named "Shengmai" (Generating Pulse) because the pulse fills with Qi and weakens without it. One tonifies, one clears, one astringes; thus, the method of nourishing Qi is complete. It is most suitable for emaciated and deficient individuals to take long-term in summer. Li Dongyuan states: Adding Huangqi (Astragali Radix) and Gancao in summer makes one's strength surge. Sun Simiao says: One must take Wuweizi in summer to tonify the Qi of the Five Zang organs. Kou Zongshi says: Maidong, Wuweizi, and Gouqi are all agents of Shengmai. Thus, a formula using Wuweizi and Gouqi decocted as tea is very suitable for treating summer deficiency diseases with fatigue, poor appetite, dry mouth, and fever.
Qing Shu Yi Qi Tang (Clear Summerheat and Tonify Qi Decoction)
Treats damp-heat steaming during late summer, manifesting as poor appetite and fatigue (caused by damp-heat damaging the Spleen), epigastric fullness and loose stools (Spleen failure to transform leads to fullness; Spleen affected by dampness leads to loose stools), heavy body and pain (Damp damages muscles, causing heaviness; damp-heat combats, causing joint pain), fever and profuse sweating (Summerheat harasses Wei Qi), thirst and vexation, yellow-red urine (Summerheat damages Lungs causing thirst; Summerheat damages Heart causing vexation and red urine), and weak pulses in all six positions.
Renshen (Ginseng Radix et Rhizoma), Huangqi (Astragali Radix), Baizhu (Atractylodis Macrocephalae Rhizoma), Chenpi (Citri Reticulatae Pericarpium), Gancao (Licorice Root), Danggui (Angelicae Sinensis Radix), Shengma (Cimicifugae Rhizoma), Gange (Puerariae Lobatae Radix) [This is Buzhong Yiqi Tang minus Chaihu, replaced by Gange. Used here to boost Stomach Qi upward to treat deficiency diarrhea], Maoyu (Atractylodis Rhizoma), Huangbai (Phellodendri Cortex) [This is Ermiao San combined with Zexie to treat damp-heat], Zexie (Alismatis Rhizoma), Qingpi (Citri Reticulatae Pericarpium Viride), Shenqu (Massae Fermentatae Medicamentosa) [Descends Qi and aids digestion], Maidong (Ophiopogonis Radix), Wuweizi (Schisandrae Fructus) [Combined with Renshen forms Shengmai San to rescue Lungs damaged by summerheat].
This formula Tonifies the Middle and strengthens Wei to dispel damp-heat. It is suitable for regular use in summer by those with pale complexion and internal deficiency, regardless of whether they suffer from summerheat.
Huanglian Jiedu Tang (Coptis Decoction to Relieve Toxicity) [See Shanghan section]
Treats all summerheat-heat syndromes in summer. It may be combined with Baihu Tang and modified according to symptoms.
This is a formula for treating Excess Fire. Jiayan states: No season presents more complex and severe illnesses than summer. The sun's summerheat, the sky's heat, and the earth's dampness merge intermittently. When dispersed, wind moves within, overcoming dampness and resolving steaming, so suffering is unnoticed. When merged, sky heat descends and earth dampness ascends. Humans in the intersection of these qi suffer intense steaming with no refuge, often experiencing vexation, mental confusion, skin prickly heat, chest acne, facial boils, and even swelling, toxins, carbuncles, and ulcers. There may be redness and swelling of the head, neck, throat, or legs/feet extending several inches, making walking impossible. Generally, cooling is appropriate to resolve summerheat toxicity. Once heat resolves, redness and swelling subside without pus or blood. There may also be blisters all over the body, like peaches or plums, bowls or cups, crystal-clear and thin, containing foul-smelling fluid. This is damp-heat water flooding the skin. This formula, modified, is also suitable for treatment.
Tunru Yin (Perilla Leaf Decoction)
Treats summer cases of seeking coolness and drinking cold, where Yang Qi is suppressed by Yin-cold, presenting with headache, fever, aversion to cold, and anhidrosis (all exterior signs of catching cold while seeking coolness, i.e., "body hot as burning charcoal, resolved by sweating"). Vomiting, diarrhea, and abdominal pain (This is due to cold drinks damaging the Spleen and Stomach, representing interior signs).
Xiangru (Elsholtziae Spica) [Acrid-warm, releases Yang Qi. Herb for releasing exterior in summer. 1–2 qian], Houpo (Magnoliae Officinalis Cortex) [Warms Spleen/Stomach, stops abdominal pain, stir-fried with ginger juice. 1 qian], Bian Dou (Vigna Radiata Seed) [Tonifies Spleen/Stomach, stops vomiting/diarrhea, stir-fried 2–3 qian. Omit if exterior signs exist]. For severe exterior signs, add Fangfeng (Saposhnikoviae Radix) and Bohe (Menthae Haplocalycis Herba). If anhidrosis persists, add Ziye (Perillae Folium) [When biased toward exterior, exterior-releasing herbs are chief]. For severe interior signs, add Chenpi (Citri Reticulatae Pericarpium), Fuling (Poria), Muxiang (Aucklandiae Radix), and Sharen (Amomi Fructus Rotundus) [When biased toward interior, interior-regulating herbs are chief]. If accompanied by vexation and red urine (Due to latent summerheat trapped by cold), add Huanglian (Coptidis Rhizoma) or Yiyuan San [To clear latent summerheat]. For deficiency, add Renshen (Ginseng Radix et Rhizoma) [Method of Shiwei Xiangru Yin].
This is a formula for releasing the exterior and harmonizing the interior in summer. Seeking coolness in large halls suppresses Yang Qi with Yin-cold, causing headache, fever, aversion to cold, and anhidrosis—this is exterior, not interior. Overeating raw/cold foods damages the Stomach, causing vomiting, diarrhea, and abdominal pain—this is interior, not exterior. Both involve cold injury, but the difference between exterior and interior dictates different medications. Jiayan also states: For cholera-like vomiting/diarrhea caused by exposing oneself to summerheat, clearing summerheat is primary; for those caused by avoiding summerheat (by excessive cooling), harmonizing and warming the Middle is primary. This distinction must not be ignored.