气寒，味甘、辛，微寒。大寒。无毒。
入手太阴经、少阳经，足阳明经。
《象》云∶治足阳明经中热，发热，恶热，燥热，日晡潮热，自汗，小便浊赤，大渴引
饮，肌肉壮热，苦头痛之药，白虎汤是也。善治本经头痛，若无此有余证，勿用。
《心》云∶细理白泽者良，甘寒。胃经大寒药，润肺除热，发散阴邪，缓脾益气。
《珍》云∶辛甘，阴中之阳。止阳明经头痛。胃弱不可服。下牙痛，须用香白芷为引。
《本草》云∶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。除时气头痛，身热，三焦大热，皮肤热，肠胃中膈气。解肌发汗，止消渴烦逆，
腹胀，暴气喘息，咽热。亦可作浴汤。
太上云∶石膏发汗。辛寒，入手太阴也。
《东垣》云∶微寒，足阳明也。又治三焦皮肤大热，手少阳也。仲景治伤寒阳明证，身热，
目痛鼻干，不得卧。身
已前，胃之经也；胸，胃肺之室。邪在阳明，肺受火制，故用辛寒以清肺，所以号为白虎汤
也。鸡子为之使。恶莽草、
马目毒公。
《药性论》云∶石膏，使。恶巴豆。《唐本》注∶疗风去热，解肌。
气寒，味甘。大寒。无毒。
入足太阳经。
《象》云∶治前阴不利，性沉重，能泄上气令下行。故曰滑则利窍。不可与淡渗同用。
白者佳。杵细、水飞用。
《本草》云∶主身热泄 ，女子乳难，癃闭。利小便，荡肠胃积聚寒热，益精气。通九
窍六腑津液，去留结，止渴，令人利中。入足太阳。滑能利窍，以通水道，为至燥之剂。猪
苓汤，用滑石与阿胶同为滑利，以利水道。葱、豉、生姜同煎去渣，澄清以解利。淡味渗泄
为阳，解表、利小便也。若小便自利，不宜以此解之。
《衍义》云∶暴吐逆，不下食，以生细末二钱匕，温水调服，后以热面压之。
[Shigao (Gypsum Fibrosum)]
Properties and Flavor: Cold in nature, sweet and acrid in flavor, slightly cold (some versions consider it extremely cold). Non-toxic.
Meridian Tropism: Enters the Hand-Taiyin Lung Meridian, Hand-Shaoyang Sanjiao Meridian, and Foot-Yangming Stomach Meridian.
Li Dongyuan stated: It is used to treat heat in the Foot-Yangming Stomach Meridian, such as fever, aversion to heat, dryness-heat, tidal fever at Dingwu time (3-5 PM), spontaneous sweating, turbid and dark urine, extreme thirst with desire to drink, intense heat in muscles, and severe headache. The formula is Baihu Tang (White Tiger Decoction). It effectively treats headaches caused by this meridian; if these excess heat syndromes are absent, it should not be used.
Wang Haogu stated: Gypsum with fine texture and bright white luster is of good quality. Sweet and cold in nature. It is an extremely cold herb for the Stomach Meridian, capable of moistening the Lungs and clearing heat, dispersing Yin pathogens, relaxing the Spleen and boosting Qi.
Zhang Congzheng stated: Acrid and sweet in flavor, belonging to Yang within Yin. It stops headaches in the Yangming Meridian. It should not be taken by those with weak Stomach Qi. For lower toothache, Xiangbaizhi (Aucklandiae Radix) must be used as a guiding herb.
Bencao states: It mainly treats wind-stroke with alternating chills and fever, rebellious Qi below the heart, palpitations and wheezing, dry mouth and scorched tongue, dyspnea, firm and painful abdomen, expelling evil spirits (referring to mental abnormalities or strange diseases), and treating postpartum conditions and metallic wounds. It removes headaches and body heat caused by epidemic febrile diseases, excessive heat in the Sanjiao, skin heat, and diaphragmatic Qi in the stomach and intestines. It releases the muscle layer and induces sweating, stops polydipsia and irritability, abdominal distension, sudden asthma, and hot throat. It can also be used to make bathing decoctions.
Taishang stated: Gypsum induces sweating. Acrid and cold, enters the Hand-Taiyin Lung Meridian.
Li Dongyuan stated: Slightly cold, enters the Foot-Yangming Stomach Meridian. It also treats severe heat in the Sanjiao and skin, entering the Hand-Shaoyang Sanjiao Meridian. Zhang Zhongjing treated Yangming syndrome in Shanghan (Cold Damage) with symptoms of body heat, eye pain, nasal dryness, and inability to sleep. The anterior part of the body is where the Stomach meridian passes; the chest is the residence of the Stomach and Lungs. When pathogenic factors are in the Yangming Meridian, the Lungs are constrained by Fire, so acrid-cold herbs are used to clear the Lungs; hence the formula is named Baihu Tang (White Tiger Decoction). Ji Zi (Egg White) serves as its assistant herb. It is incompatible with Mangcao (Aconiti Lateralis Radix Preparata? Note: Context suggests specific incompatibility, likely referring to specific toxic herbs or misinterpretation of ancient texts, but strictly translating "Mangcao" and "Ma Mu Du Gong") and Ma Mu Du Gong.
Yaoxing Lun stated: Gypsum acts as a guiding herb. Incompatible with Badou (Crotonis Fructus). Tang Bencao annotation: Treats wind and removes heat, releases the muscle layer.
[Huaishi (Talcum)]
Properties and Flavor: Cold in nature, sweet in flavor. Extremely cold. Non-toxic.
Meridian Tropism: Enters the Foot-Taiyang Bladder Meridian.
Li Dongyuan stated: It treats difficulty in urination from the anterior yin. Its nature is heavy, capable of draining rebellious Qi from the upper body and directing it downward. Thus it is said that "slippery substances open orifices." It should not be used together with bland diuretics. White ones are preferred. It should be pounded into fine powder and processed by water flotation (shui fei).
Bencao states: It mainly treats body heat with diarrhea, difficulty in lactation in women, and stranguria. It promotes urination, sweeps away accumulated cold and heat in the stomach and intestines, and benefits Essence and Qi. It unblocks the fluids of the nine orifices and six fu organs, removes stagnation, stops thirst, and promotes smoothness. It enters the Foot-Taiyang Bladder Meridian. The slippery property opens orifices to unblock water passages, acting as a very drying agent. In Zhuling Tang, Huashi (Talcum) is used with Ejiao (Donkey-hide Gelatin) to provide slipperiness and promote water passage. Decocted with Congbai (Scallion Stem), Chichi (Fermented Soybean), and Shengjiang (Fresh Ginger), filtered, clarified, and taken to release the exterior and promote urination. Bland and draining properties belong to Yang, capable of releasing the exterior and promoting urination. If urination is already free, it is not suitable to use this herb to promote drainage.
Kou Zongshi stated: For sudden vomiting and regurgitation with inability to eat, take two qianbi of raw, finely powdered Talcum, mix with warm water and ingest, then follow with hot noodles to suppress the medication's effect.