轻、发汗。
辛苦而温。（僧继洪云∶中牟产麻黄地、冬不积雪、性热可知。）入足太阳。（膀胱。）兼
走手
少阴阳明。（心、大肠。）而为肺家专药。能发汗解表。去营中寒邪。疏通气血。利九窍。开
毛孔。治伤寒头痛。恶寒无汗。（东垣曰∶十剂云∶轻可去实、葛根麻黄之类是也、邪客
皮毛、腠理闭拒、营卫不行、故谓之实、二药轻清可去之、时珍曰∶麻黄太阳经药、兼入肺
经、肺主皮毛、葛根阳明经药、兼入脾经、脾主肌肉、二药皆轻扬升发、而所入不同、好古
曰∶麻黄汤治卫实、桂枝汤治卫虚、虽皆太阳经药、其实营卫药也、心主营为血、肺主卫为
气、故麻黄为手太阴肺之剂、桂枝为手少阴心之剂、时珍曰∶仲景治伤寒、无汗用麻黄、有
汗用桂枝、未有究其精微者、津液为汗、汗即血也、在营则为血、在卫则为汗、寒伤营、营
血内涩、不能外通于卫、卫气固闭、津液不行、故无汗、发热而恶寒、风伤卫、卫气外泄、
不能内护于营、营气虚弱、津液不固、故有汗、发热而恶风、然风寒皆由皮毛而入、皮毛、
肺之合也、盖皮毛外闭、则邪热内攻、故用麻黄甘草、同桂枝、引出营分之邪、达之肌表、
佐以杏仁、泄肺而和气、汗后无大热而喘者、加石膏、活人书、夏至后加石膏知母、皆泄肺
火之药、是麻黄汤虽太阳发汗重剂、实散肺金火郁之药、腠理不密、则津液外泄而肺气虚、
虚则补其母、故用桂枝同甘草、外散风邪以救表、内伐肝木以防脾、佐以芍药、泄木而固脾
、使以姜枣、行脾之津液、而和营卫、下后微喘者、加浓朴杏仁、以利肺气也、汗后脉沉迟
者、加人参、以益肺气也、有火者加黄芩、为阳旦汤、以泻肺实也、是桂枝汤虽太阳解肌轻
剂、实为理脾救肺之药也。）温疟。咳逆上气。（风寒郁于肺经、经曰∶诸气 郁、皆属于肺
。）痰哮气喘。（哮证宜泻肺、然惟气实者、可暂用。）皮肉不仁。水肿风肿。唯冬月在表。
真有寒邪者宜之。若非冬月。或无寒邪。或寒邪在里。或伤风等证。虽发热恶寒。不头疼身
疼
皆不可用。虽可汗之证。亦不宜过剂。（汗为心液、过汗则心血为
之动、或亡阳、或血溢、而成大患、丹溪以人参麻黄同用、亦攻补法也。）发汗用茎。去节
。煮十余沸。掠去浮沫。或用醋汤略泡。晒干。亦有用蜜水炒者。（庶免太发。）止汗用根节。
虚、
梦中出汗为盗汗、属阴虚、用麻黄根、蛤粉、粟米等分为末、
袋盛扑之、佳、时珍曰∶麻黄发汗、驶不能御、根节止汗、效如影响、物理不可测如此、自
汗有风湿、伤风、风温、气虚、血虚、胃热、痰饮、中暑、亡阳、柔痉等证、皆可加用、盖
性能行周身肌表、引药至卫分而固腠理也。汗虽为心液、然五脏亦各有汗、经曰∶饮食饱
甚、汗出于胃、惊而夺精、汗出于心、持重远行、汗出于肾、疾走恐惧、汗出于肝、摇体劳
苦、汗出于脾。）浓朴、白薇为使。恶辛夷、石膏。（内外障翳、麻黄根一两、归身一钱、同
炒黑色、入麝香一厘、为末、 鼻频用、效。）
（麻黄）味轻，能发汗。
味辛苦而性温。（僧人继洪说：中牟出产麻黄的地方，冬天不积雪，可知其性热。）归入足太阳经（膀胱经）。兼走手少阴、手阳明经（心经、大肠经），是肺经的专用药。能够发汗解表，祛除营分中的寒邪，疏通气血，通利九窍，开泄毛孔，治疗伤寒引起的头痛、恶寒无汗。（李东垣说：《十剂》中说：轻可去实，葛根、麻黄之类就是。邪气客于皮毛，腠理闭拒，营卫运行不畅，所以称为“实”，这两味药轻清可以去除它。李时珍说：麻黄是太阳经药，兼入肺经，肺主皮毛；葛根是阳明经药，兼入脾经，脾主肌肉。两药都轻扬升发，但所入经络不同。王好古说：麻黄汤治疗卫分实证，桂枝汤治疗卫分虚证，虽然都是太阳经药，其实是调理营卫的药。心主营属血，肺主卫属气，所以麻黄是手太阴肺经的药剂，桂枝是手少阴心经的药剂。李时珍说：张仲景治疗伤寒，无汗用麻黄，有汗用桂枝，没有人探究其中的精微之处。津液化为汗，汗即血也，在营分则为血，在卫分则为汗。寒邪伤营，营血内涩，不能外通于卫，卫气固闭，津液不行，所以无汗，发热且恶寒；风邪伤卫，卫气外泄，不能内护于营，营气虚弱，津液不固，所以有汗，发热且恶风。然而风寒都由皮毛而入，皮毛是肺之合。皮毛外闭，则邪热内攻，所以用麻黄、甘草，同桂枝一起，引出营分之邪，达于肌表，佐以杏仁，泄肺气而和气。发汗后没有大热却喘息的，加石膏。《活人书》说夏至后加石膏、知母，都是泄肺火的药。这说明麻黄汤虽然是太阳经发汗的重剂，实际上是散肺金火郁的药。腠理不密，则津液外泄而肺气虚，虚则补其母，所以用桂枝同甘草，外散风邪以救表，内伐肝木以防脾，佐以芍药，泄木气而固脾气，使以姜枣，行脾之津液，而调和营卫。下法后微喘的，加厚朴、杏仁，以利肺气。发汗后脉沉迟的，加人参，以益肺气。有火的加黄芩，成为阳旦汤，以泻肺实。这说明桂枝汤虽然是太阳经解肌的轻剂，实际上是调理脾胃、救助肺脏的药。）治疗温疟，咳逆上气。（风寒郁结于肺经，《内经》说：各种气机郁滞，都归属于肺。）痰哮气喘。（哮证宜泻肺，然而只有气实的患者，才可暂时使用。）皮肉麻木不仁，水肿，风肿。只有在冬季在表，真正有寒邪的患者适宜使用。如果不是冬季，或者没有寒邪，或者寒邪在里，或者伤风等证，虽然发热恶寒，但不头疼身疼，都不可用。即使是可发汗的证候，也不宜过量。（汗为心之液，过汗则心血为之动荡，或亡阳，或血溢，而成大患。朱丹溪主张将人参与麻黄同用，也是攻补兼施的方法。）发汗用茎，去掉节。煮十余沸，掠去浮沫。或用醋汤略泡，晒干。也有用蜜水炒制的。（以免发汗太过。）止汗用根节。虚证，梦中出汗为盗汗，属阴虚，用麻黄根、蛤粉、粟米等分为末，袋盛扑之，佳。李时珍说：麻黄发汗，迅猛无法抵御；根节止汗，效果如影随形，物理不可测如此。自汗有风湿、伤风、风温、气虚、血虚、胃热、痰饮、中暑、亡阳、柔痉等证，皆可加用，因为其性能行周身肌表，引药至卫分而固腠理。汗虽为心液，然五脏亦各有汗，《内经》说：饮食饱甚，汗出于胃；惊而夺精，汗出于心；持重远行，汗出于肾；疾走恐惧，汗出于肝；摇体劳苦，汗出于脾。）厚朴、白薇为使药。畏恶辛夷、石膏。（内外障翳，麻黄根一两，当归身一钱，同炒黑色，入麝香一厘，为末，点鼻频用，有效。）
(Light in nature, induces sweating.)
Bitter and pungent, warm in temperature. (Monk Jihong stated: In Zhongmu where Ephedrae Herba is produced, snow does not accumulate in winter, indicating its hot nature.) Enters the Foot-Taiyang channel (Bladder). Also traverses the Hand-Shaoyin and Hand-Yangming channels (Heart, Large Intestine), serving as a specific medicine for the Lung. It can induce sweating to release the exterior, dispel cold pathogens from the Ying (Nutritive) level, unblock Qi and Blood, benefit the nine orifices, open pores, and treat headache and aversion to cold with absence of sweating caused by Cold Damage (Shanghan). (Li Dongyuan said: The "Ten Categories" states that "Lightness can remove excess," exemplified by Puerariae Radix and Ephedrae Herba. When pathogens lodge in the skin and hair follicles, the interstices close and reject, causing Ying and Wei (Defensive) circulation to stagnate, thus termed "excess." These two medicines are light and clear, capable of removing it. Li Shizhen said: Ephedrae Herba is a Taiyang channel medicine, also entering the Lung channel; the Lung governs skin and hair follicles. Puerariae Radix is a Yangming channel medicine, also entering the Spleen channel; the Spleen governs muscles. Both medicines are light, ascending, and dispersing, but enter different channels. Wang Haogu said: Mahuang Tang treats Wei excess, Guizhi Tang treats Wei deficiency. Although both are Taiyang channel medicines, they actually regulate Ying and Wei. The Heart governs Ying as Blood, the Lung governs Wei as Qi. Thus, Ephedrae Herba is a formula for the Hand-Taiyin Lung, while Cinnamon Twig is a formula for the Hand-Shaoyin Heart. Li Shizhen said: Zhang Zhongjing treated Cold Damage; for absence of sweating, he used Ephedrae Herba; for presence of sweating, he used Cinnamon Twig. Few have investigated its subtleties. Body fluids transform into sweat; sweat is blood. In Ying it is blood, in Wei it is sweat. Cold injures Ying; Ying blood becomes stagnant internally, unable to communicate externally with Wei; Wei Qi is solidly closed, body fluids do not circulate, hence no sweating, fever, and aversion to cold. Wind injures Wei; Wei Qi leaks externally, unable to protect internally Ying; Ying Qi is weak, body fluids are not secure, hence sweating, fever, and aversion to wind. However, wind and cold both enter via skin and hair follicles; skin and hair follicles are the exterior correspondence of the Lung. If the exterior is closed, pathogenic heat attacks internally. Therefore, Ephedrae Herba and Licorice Root are used together with Cinnamon Twig to draw out pathogens from the Ying level and bring them to the muscle surface, assisted by Apricot Seed to drain Lung Qi and harmonize Qi. After sweating, if there is no high fever but wheezing, add Gypsum. The "Huoren Shu" states that after the Summer Solstice, Gypsum and Anemarrhena Rhizome are added, which are medicines to drain Lung fire. This shows that although Mahuang Tang is a heavy sweating agent for the Taiyang channel, it is actually a medicine to disperse Lung Metal fire depression. If interstices are not tight, body fluids leak externally and Lung Qi becomes deficient. Deficiency requires tonifying the mother element; therefore, Cinnamon Twig is used with Licorice Root to disperse wind pathogens externally to rescue the exterior, and subdue Liver Wood internally to prevent invasion of the Spleen, assisted by White Peony Root to drain Wood and consolidate Spleen, guided by Ginger and Jujube to move Spleen fluids and harmonize Ying and Wei. After purgation, if there is slight wheezing, add Magnolia Bark and Apricot Seed to benefit Lung Qi. After sweating, if the pulse is deep and slow, add Ginseng Root to benefit Lung Qi. If there is fire, add Scutellaria Root to form Yangdan Tang to drain Lung excess. This shows that although Guizhi Tang is a light muscle-releasing agent for the Taiyang channel, it is actually a medicine to regulate the Spleen and rescue the Lung.) Treats warm malaria, cough with rebellious Qi. (Wind-cold stagnates in the Lung channel; the Classic says: All Qi stagnations belong to the Lung.) Phlegmatic asthma and wheezing. (Asthma should be drained by the Lung, however, only patients with Qi excess can temporarily use it.) Numbness of skin and flesh, edema, wind-swelling. Suitable only in winter when the pathogen is in the exterior and truly involves cold pathogens. If not in winter, or without cold pathogens, or if cold pathogens are in the interior, or in cases of wind-strike etc., even if there is fever and aversion to cold, but without headache and body ache, it must not be used. Even in syndromes suitable for sweating, it should not be overdosed. (Sweat is the fluid of the Heart; excessive sweating causes disturbance of Heart Blood, leading to collapse of Yang or hemorrhage, resulting in major disasters. Zhu Danxi advocated using Ginseng Root together with Ephedrae Herba, which is a method of attacking and tonifying simultaneously.) For inducing sweating, use the stem, remove the nodes. Boil for more than ten boils, skim off the floating foam. Or briefly soak in vinegar water, then dry in the sun. Some are stir-fried with honey water. (To avoid excessive sweating.) To stop sweating, use the root nodes. For deficiency, night sweats occurring during dreams belong to Yin deficiency. Use equal parts of Ephedrae Radix et Rhizoma, Trichosanthes Powder, and Millet ground into powder, placed in a bag and dusted on the body, which is excellent. Li Shizhen said: Ephedrae Herba induces sweating so rapidly it cannot be controlled; root nodes stop sweating, effective as shadow follows form. The principles of physical properties are unfathomable. Spontaneous sweating includes syndromes such as wind-damp, wind-strike, wind-warmth, Qi deficiency, Blood deficiency, Stomach heat, phlegm-fluid retention, summerheat stroke, collapse of Yang, and flexible spasm; all can add this herb because its nature travels through the whole body's muscle surface, guiding medicines to the Wei level to consolidate interstices. Although sweat is the fluid of the Heart, each of the Five Zang organs has its own sweat. The Classic says: When food intake is excessive, sweat comes from the Stomach; when startled and essence is lost, sweat comes from the Heart; when carrying heavy loads and traveling far, sweat comes from the Kidney; when running fast and fearing, sweat comes from the Liver; when shaking the body and working hard, sweat comes from the Spleen.) Magnolia Bark and Anemarrhena Rhizoma serve as guides. Adversely reacts with Magnolia Flower and Gypsum. (For internal and external cataracts, one tael of Ephedrae Radix et Rhizoma and one qian of Angelica Sinensis Radix are stir-fried together until black, mixed with one li of Musk, ground into powder, applied frequently to the nose, effective.)