（本经中品）
【气味】辛，微寒，无毒。
【主治】主中风寒热，心下逆气，惊喘，口干舌焦，不能息，腹中坚痛，除邪鬼，产乳
金疮
【核】曰∶出齐卢山，及鲁蒙山，剡州、彭城、钱唐亦有之。生石中，大块作层，细文
短密，宛若束针，洁白如膏，松软易碎，烧之白烂如粉也。一种硬者生地中，枚块作棱，直
理坚白，击之段段横解，墙壁光亮，烧之易散，不作粉也。别有一种，细文长密，宛若束丝
者，理石也。一种作块无棱，横理坚白，击之方解，烧之 散作粉者，方解石也。昔人所谓
长石，即石膏之硬者；所谓寒水石，即石膏之软者。而理石、方解石，气味都辛寒，但不若
石膏之软者，能解肌发汗为异耳。修治，石臼中捣研成粉，罗过，生甘草水飞两遍，澄清去
水，晒干再研。鸡子为之使。恶莽草、巴豆、马目毒公。及铁。
【 】曰∶石以止为体，膏以释为用。质之宁谧，气之微寒，即体之止；文之理腠，味
之辛解，即用之释。体用互显者也，但止释有时，故体用各有先后尔。或因似体之止，则显
用以释之，或因似用之释，则显体以止之。此即从而逆，逆而从，反佐以取之之法也。如风
性动摇，从之以用，逆之以体；寒性劲敛，从之以体，逆之以用，此从逆寒风定动之本性，
非从逆寒风寒化之本气也。以性无迁变，气有反从，反从者，反乎本气之寒，从乎标象之阳，
则为病热之热也。则凡结而欲解者宜矣。结而欲下者，非所宜也。与麻黄、桂枝、葛根，解
发之用相同。寒热从逆之气为别异耳。主治诸证，悉以体止用释，逆热从寒，反复分疏，莫
不迎刃而解。并可推暑性之欲降，火性之欲炎，燥性之欲濡，湿性之欲流，与腑脏形骸，血
气窍穴，欲止欲释者，详审合宜，为效颇捷。否则灾害并至，慎之慎之。
（暑性之欲降，转炎敲为清肃；火性之欲炎，火空则发，以张夏大之出令也。）
【《神农本草经》列为中品药物】
【气味】味辛，性微寒，无毒。
【主治功效】主要治疗中风引起的寒热症状，心下部的气逆上冲，惊恐气喘，口干舌焦，呼吸急促困难，腹部坚硬疼痛，驱除邪祟鬼魅，以及产后乳疾和金创（金属利器造成的创伤）。
【考证辨析】卢之颐说：石膏产于齐卢山，以及鲁蒙山，剡州、彭城、钱唐等地也有出产。它生于石头之中，大块呈层状结构，纹理细短密集，宛如一束束针尖，颜色洁白如油脂，质地松软易碎，燃烧后变成白烂如粉的状态。有一种较硬的石膏生于地下，呈枚块状带棱角，纹理笔直且坚白，敲击时横向断裂成段，断面光亮如墙壁，燃烧后容易散开，不形成粉末。另外还有一种，纹理细长密集，宛如一束丝线的，称为理石。还有一种呈块状无棱角，横向纹理坚白，敲击时方形断裂，燃烧后散开成粉的，称为方解石。古人所说的“长石”，就是石膏中较硬的那种；所说的“寒水石”，就是石膏中较软的那种。而理石和方解石，气味也都属于辛寒，只是不像石膏中较软的那种，具有解除肌表邪气、发汗的功效，这是它们的不同之处。炮制方法：在石臼中捣碎研磨成粉，筛过，用生甘草水飞法处理两遍，澄清后去掉水分，晒干后再研磨。鸡蛋清是它的引药（使药）。忌与莽草、巴豆、马目毒公（一种有毒植物）及铁器同用。
【理论阐释】卢之颐说：石头以静止为体性，膏脂以融释为功用。质地的宁静谧止，气味的微寒，体现了“体”的静止特性；纹理通达腠理，味道的辛散解结，体现了“用”的融释特性。体与用相互显现，但静止与融释各有其时机，所以体与用各有先后顺序。或许因为看似具备静止的体性，就显发其融释的功用；或许因为看似具备融释的功用，就显发其静止的体性。这就是顺从病势而逆向治疗，或逆向病势而顺从治疗，通过反佐来取得疗效的方法。例如风性动摇，顺应其用（发散），逆转其体（静止）；寒性劲急收敛，顺应其体（凝敛），逆转其用（发散）。这是针对寒风定动之本性的顺逆调节，而非针对风寒化生之本气的顺逆调节。因为本性没有迁变，但气机有反向随从的情况，所谓“反从”，是指违背本气的寒性，随从标象的阳热，从而产生类似病热的热象。那么，凡是郁结想要解散的情况，使用石膏是适宜的。如果是郁结想要攻下的情况，则不适宜。石膏与麻黄、桂枝、葛根一样，都有解发表邪的作用，区别仅在于寒热顺逆的气机不同罢了。主治的各种证候，都是依据石膏体止用释的特性，逆治热邪，顺从寒性，反复分析疏解，无不迎刃而解。并且可以推演暑性想要下降，火性想要炎上，燥性想要濡润，湿性想要流动，以及脏腑形骸、气血窍穴，哪些需要静止，哪些需要融释，详细审察并合乎宜理，疗效颇为快捷。否则灾害并至，务必谨慎，务必谨慎。
（暑性想要下降，将炎酷敲击转为清肃；火性想要炎上，火在空处则发散，以张扬夏季盛大的出令之气。）
[Classified as Middle Grade in the *Shennong Bencao Jing*]
【Flavor and Nature】Pungent, slightly cold, non-toxic.
【Indications】Primarily treats wind-stroke with alternating chills and fever, rebellious Qi rising in the epigastrium, frightful panting, dry mouth and scorched tongue, dyspnea (difficulty breathing), hardness and pain in the abdomen, expels evil spirits, and treats postpartum conditions and metal wounds.
【Verification and Analysis】Lu Zhiyi states: Shihao (Gypsum Fibrosum) is produced in Qilu Mountain and Lumen Mountain, and also found in Yanzhou, Pengcheng, and Qiantang. It grows within rocks, forming large layered blocks. The texture is fine, short, and dense, resembling a bundle of needles. It is white and clean like paste, soft and brittle, and when burned, turns into white powder like ash. There is a harder variety that grows underground, forming prismatic blocks with straight, hard, and white grain; when struck, it breaks transversely into segments with a wall-like luster on the fracture surface. When burned, it scatters easily without forming powder. Another variety has long, dense grains resembling a bundle of silk threads, known as Lizhi (Alabaster). Yet another variety forms blocks without edges, with hard and white horizontal grain, breaking into square pieces when struck, and scattering into powder when burned, known as Fangjieshi (Calcite). What ancients called "Changshi" refers to the harder form of Shihao; what they called "Han Shui Shi" refers to the softer form of Shihao. Lizhi and Fangjieshi both have pungent and cold flavors, but unlike the softer Shihao, they lack the ability to release the muscle layer and induce sweating, which is their distinct difference. Processing: Pounded and ground into powder in a stone mortar, sifted, then processed twice using the water-floating method with raw Gancao (Licorice Root) water. After clarification, remove the water, sun-dry, and grind again. Ji Zi (Egg White) serves as its guiding herb (Shi Yao). It is incompatible with Mangcao (Aconitum brachypodum root), Badou (Croton Seed), Mumu Dougong (a toxic plant), and iron.
【Theoretical Explanation】Lu Zhiyi states: Stone possesses stillness as its substance (Ti), while paste possesses dissolution/release as its function (Yong). The tranquility and quietude of its quality, along with its slightly cold nature, manifest the stillness of its substance. The texture penetrating the interstices and the pores, along with its pungent flavor resolving stagnation, manifest the releasing function. Substance and function mutually reveal each other, yet stillness and release occur at specific times, so substance and function have their respective priorities. Perhaps because it appears to possess the substance of stillness, its function of release is manifested; perhaps because it appears to possess the function of release, its substance of stillness is manifested. This is the method of treating against the trend by following it, or following the trend by opposing it, utilizing counter-assistance to achieve efficacy. For instance, Wind nature is turbulent; one follows its function (dispersal) and opposes its substance (stillness). Cold nature is vigorous and contracting; one follows its substance (condensation) and opposes its function (release). This addresses the inherent nature of wind and cold regarding stability and movement, not the inherent Qi of wind-cold transformation. Since nature does not change, but Qi may reverse-follow, "reverse-following" means going against the inherent cold Qi and following the superficial Yang manifestation, thereby generating heat similar to pathological heat. Therefore, for conditions involving stagnation that desire resolution, Shihao is appropriate. However, for stagnation requiring purgation, it is inappropriate. Its use in releasing the exterior is similar to that of Mahuang (Ephedrae Herba), Guizhi (Cinnamon Twig), and Gegen (Puerariae Lobatae Radix); the difference lies only in the opposing Qi of cold and heat. All indications are treated by leveraging Shihao's substance of stillness and function of release, opposing heat and following cold, analyzing and dispersing repeatedly, resolving difficulties effortlessly. One can extrapolate this to Summerheat desiring descent, Fire desiring flaming upward, Dryness desiring moistening, Dampness desiring flow, and the desires for stillness or release in organs, viscera,形体 (body structure), Blood, Qi, and acupoints. By carefully examining and aligning with these principles, efficacy is swift. Otherwise, disasters will converge; be cautious, be cautious.
(The Summerheat nature desires descent, transforming scorching heat into clarity and肃ness (cleanse and descend); the Fire nature desires flaming upward, and fire in emptiness expands, magnifying the expansive command of summer.)