自汗者，不因发散而自然汗出也。卫气者，卫护皮肤，肥实腠理，禁固津液，使不得妄泄也。痘疹之火，由里达
表，干于卫气，皮肤为之缓，腠理为之疏，津液外泄，故自汗也，凡病自汗，宜遽止之。疮疹初出，自汗实为美证，
乃阴阳气和，荣卫通畅，邪气不留，易出而解也。又，心主汗，诸疮皆属于心，自汗出者，毒瓦斯外泄也，虽然热之甚者，
亦为汗解，身复清凉，此毒散也。若汗出不止，其热反剧，此邪气并于阳而阳虚，宜敛汗固表，清热解毒，使卫气充实，
无痒塌溃烂之患。保元汤（大法）当归六黄汤（盗汗）主之。如疮已收较，痂皮脱落自汗者，此气虚也，宜补阳救
阴，使气无泄，十全大补汤（汗）主之。若更不止，调败蒲散同服，外用温粉扑法。薛
氏云∶靥后最宜审治，若血虚者，用当归补血汤（虚热）。气虚者，用四君子汤加黄 。气血不足者，十全大补汤。
饮食自汗者，小异功散（吐泻）加黄连、五味子、乌梅肉。睡中汗出，心有热也，其汗上至头，下至颈，不过胸者，乃
六
阳虚汗也，不须治之。上至颈，下至脐者，此胃虚也，保元汤（即参 饮见大法）不止，调败蒲散同服。自汗者，
血之所化，阴气不能闭藏，所以睡则汗出，痘家当以补血为主，若当归补血汤、六味地黄丸、八珍汤、人参养荣汤之类，
皆可因证施治。自汗面赤作渴，手足 汗多者，胃热也，泻黄散（脾）人参白虎汤（发热）加黄连主之。诸证退，
以小异功散加山栀仁、麦门冬调之。有食积内热自汗者，四君子加曲 。自汗发搐流涎者，肝木侮土也，小异功散
加钓藤。搐减，去钓藤加柴胡主之。丹溪谓自汗不妨，盖指初出并其汗之不甚者言耳，若汗出过多，最能虚人，
未靥之际，恐致气血虚而不能结痂，既靥之后，尤防血脱阴虚，阳无所附矣。汗出如油，发润如洗，喘不休者，此
为肺绝之候，死不治。
浮麦散
浮麦不拘多少，炒香，每服三五钱，水煎服，治胃虚自汗。
败蒲散（一名止汗散）
用故蒲扇烧灰，每服三钱，温酒调下，无时服。
温粉扑法
黄连 牡蛎粉 贝母（各半两） 粳米粉（一升）
上为细末。敷于身上。
自汗，是指没有经过发汗治疗而自然出汗的症状。卫气的作用是护卫皮肤，使腠理（皮肤纹理及毛孔）致密坚固，固摄津液，防止其无故流失。痘疹的热毒由体内达于体表，干扰卫气，导致皮肤松弛，腠理开泄，津液外泄，从而出现自汗。凡是疾病过程中出现的自汗，应当立即止汗。但在疮疹初出阶段，自汗实际上是佳兆，说明阴阳之气调和，营卫通畅，邪气无法滞留，有利于痘疹透发并痊愈。另外，心主司汗液，各种疮疡都归属于心，自汗是热毒随汗液外泄的表现。虽然热势严重时，通过出汗也能使病情缓解，身体恢复清凉，这是热毒消散的迹象。如果汗出不止，发热反而加重，这是因为邪气并入阳分导致阳气虚弱，应当采用收敛止汗、固护肌表的方法，配合清热解毒，使卫气充实，避免发生瘙痒、塌陷、溃烂等并发症。此时可用保元汤（主治大法所述之证）或当归六黄汤（主治盗汗）来治疗。如果疮疹已经收靥结痂，痂皮脱落后仍自汗，这是气虚所致，应当补益阳气以救阴液，使气不致耗散，可用十全大补汤（主治汗证）来治疗。如果汗出仍然不止，可配合服用调败蒲散，外用温粉扑法。薛己说：痘疹结痂后最应仔细诊治，如果是血虚引起的，用当归补血汤（主治虚热）；气虚的，用四君子汤加黄芪；气血不足的，用十全大补汤。因饮食不当引起自汗的，用小异功散（主治吐泻）加黄连、五味子、乌梅肉。睡中出汗，是心有热所致，如果汗液上至头部，下至颈部，不超过胸部，这是六阳经虚导致的汗出，不需要治疗。如果汗液上至颈部，下至肚脐，这是胃虚所致，用保元汤（即参芪饮，见大法所述）治疗，若不止，配合服用调败蒲散。自汗是由血液化生的，阴气不能闭藏，所以睡觉时出汗，痘疹患者应当以补血为主，如当归补血汤、六味地黄丸、八珍汤、人参养荣汤等，都可以根据具体证候施治。自汗伴有面红、口渴、手足多汗的，是胃热所致，用泻黄散（主治脾热）或人参白虎汤（主治发热）加黄连来治疗。诸证消退后，用小异功散加山栀仁、麦门冬调理。有食积内热导致自汗的，用四君子汤加神曲。自汗伴有抽搐、流涎的，是肝木克制脾土所致，用小异功散加钩藤。抽搐减轻后，去掉钩藤，加柴胡治疗。朱丹溪认为自汗无妨，这指的是痘疹初出且汗出不多的情况。如果汗出过多，最能使人虚弱，在痘疹未结痂之前，恐怕导致气血虚弱而不能结痂；在痘疹已结痂之后，更要防止血脱阴虚，导致阳气无所依附。如果汗出如油，头发湿润如洗，气喘不停，这是肺气绝的征象，属于死证，无法治愈。
浮麦散
浮小麦不拘多少，炒香，每次服用三到五钱，用水煎服，治疗胃虚引起的自汗。
Spontaneous sweating refers to the symptom of sweating naturally without undergoing diaphoretic treatment. Wei Qi (Defensive Qi) functions to protect the skin, ensure the density and solidity of Cou Li (skin texture and pores), secure body fluids, and prevent their abnormal leakage. The heat-toxin of smallpox/rash travels from the interior to the exterior, interfering with Wei Qi, causing the skin to become lax and Cou Li to open, leading to the external leakage of body fluids, thus resulting in spontaneous sweating. In general diseases, spontaneous sweating should be stopped immediately. However, during the initial eruption of rashes, spontaneous sweating is actually a favorable sign, indicating that Yin and Yang Qi are harmonious, Ying Qi (Nutritive Qi) and Wei Qi are unobstructed, pathogenic factors cannot remain stagnant, and it facilitates the eruption and resolution of the rash. Furthermore, the Heart governs sweat, and all sores and ulcers belong to the Heart; spontaneous sweating indicates the external excretion of toxic heat. Although severe heat can also be relieved through sweating, leading to a return to normal body temperature, this signifies the dissipation of toxin. If sweating continues incessantly and fever worsens, it is because pathogenic factors have merged into the Yang aspect, causing Yang deficiency. One should employ methods to astringe sweat and consolidate the exterior, combined with clearing heat and detoxifying, to replenish Wei Qi and avoid complications such as itching, collapse, or ulceration. At this stage, Baoyuan Decoction (for conditions described in the General Principles) or Danggui Liu Huang Tang (Cinnamon Twig and Rehmannia Six-Huang Decoction, for night sweats) may be used. If the rash has crusted over and scabs fall off, yet spontaneous sweating persists, this is due to Qi deficiency. One should tonify Yang to rescue Yin, preventing Qi loss, and use Shiquan Dabu Decoction (Ten Complete Great Tonifying Decoction, for sweating disorders). If sweating remains uncontrolled, Tiao Bai Pu San (Decoction to Regulate Cattail Powder) may be taken concurrently, along with the application of Wenzhen Pufa (Warm Powder Dusting Method). Xue Ji stated: After the rash has crusted, careful treatment is essential. If caused by Blood deficiency, Danggui Buxue Tang (Angelica Sinensis and Astragalus Tonifying Blood Decoction, for deficient heat) is used; if due to Qi deficiency, Sijunzi Tang (Four Gentlemen Decoction) plus Huangqi (Astragalus Root) is used; if both Qi and Blood are insufficient, Shiquan Dabu Decoction is used. For spontaneous sweating caused by dietary irregularities, Xiaoyigong San (Minor Extra-Efficacy Powder, for vomiting and diarrhea) plus Huanglian (Coptis Rhizome), Wuweizi (Schisandra Fruit), and Wumei Rou (Mume Seed Flesh) is employed. Sweating during sleep is caused by Heat in the Heart. If sweat extends from the head to the neck but does not reach the chest, it is sweating due to deficiency of the Six Yang channels, which requires no treatment. If sweat extends from the neck to the umbilicus, it is due to Stomach deficiency, treated with Baoyuan Decoction (equivalent to Shenqi Yin, see General Principles); if ineffective, Tiao Bai Pu San is added. Spontaneous sweating originates from blood transformation; when Yin Qi fails to secure and store, sweating occurs during sleep. Patients with smallpox/rash should primarily focus on nourishing Blood. Formulas such as Danggui Buxue Tang, Liuwei Dihuang Wan (Six-Ingredient Rehmannia Pill), Bazhen Tang (Eight-Treasure Decoction), and Renshen Yangrong Tang (Ginseng and Longan Nourishing Spirit Decoction) can be applied according to specific patterns. Spontaneous sweating accompanied by facial redness, thirst, and excessive sweating on hands and feet indicates Stomach Heat, treated with Xiehuang San (Drain Yellow Powder, for Spleen heat) or Renshen Baihu Tang (Ginseng and White Tiger Decoction, for fever) plus Huanglian. After other symptoms subside, regulation can be achieved with Xiaoyigong San plus Zhizi Ren (Gardenia Seed) and Maidong (Ophiopogon Tuber). Spontaneous sweating caused by food stagnation and internal heat is treated with Sijunzi Tang plus Qu (Medicated Leaven). Spontaneous sweating accompanied by convulsions and salivation indicates Liver Wood insulting Earth (Spleen/Stomach), treated with Xiaoyigong San plus Gouteng (Uncaria Ramulus cum Uncis). Once convulsions diminish, remove Gouteng and add Chaihu (Bupleurum Root). Zhu Danxi claimed that spontaneous sweating is harmless, referring only to the initial eruption phase with mild sweating. However, excessive sweating can severely weaken the body. Before crusting, it may lead to Qi and Blood deficiency preventing scab formation; after crusting, one must guard against Blood depletion and Yin deficiency, leaving Yang without attachment. Sweating like oil, hair wet as if washed, and incessant panting are signs of Lung Qi exhaustion, representing a fatal condition that cannot be cured.
Fumai San (Floating Wheat Powder)
Floating wheat, any amount, stir-fried until fragrant. Take 3–5 qian per dose, decocted in water. Treats spontaneous sweating due to Stomach deficiency.
Baipu San (Cattail Powder, also known as Zhihan San / Stop-Sweat Powder)
Burn old cattail fans to ash. Take 3 qian per dose, mixed with warm wine. Administer at any time.
Wenzhen Pufa (Warm Powder Dusting Method)
Huanglian (Coptis Rhizome), Limonium Oyster Shell Powder (Muli Fen), Fritillaria Bulb Powder (Beimu Fen) (each 0.5 liang), Rice Flour (Jingmi Fen) (1 sheng).
Grind all ingredients into fine powder. Apply to the body.