恶菊花、玄参、白藓皮。忌猪肉，恐漏精。解巴豆毒。
大苦，大寒。入足厥阴、少阴经血分。大伐脏腑邪热，善杀虫，搜窠毒。消果积，疗泻
痢，
退胎蒸，除温疟，小儿盗汗惊疳，大人伤寒咳嗽。得川连、朱砂，治疳热霍乱。得鹅胆、鸡
子清，调涂痔疮肿痛不可忍。配栀子、猪胆，治伤寒劳复。配乌梅、灶下土，治血痢。配黄
连为末，用黄瓜一个，去瓤留盖，入药合定，面裹煨熟，去面，捣丸绿豆大，量儿大小温水
下，治小儿黄胆。同猪 、当归、甘草，治霉疮。米泔浸，柳木火焙干用。
旧根中空而枯者名片芩，又名枯芩。新根内实者名子芩，又名条芩。
龙骨、山茱萸为之使。畏丹砂、牡丹、藜芦。恶葱。
苦，寒。入手太阴、少阳、阳明经气分。泻三焦实火，祛肌表邪热，利气郁，消膈痰，
解喉腥，化斑疹，治疮疡，
通肠闭，止热痛，凉血安胎。得黄 、白蔹、赤小豆，治鼠 。得浓朴、川连，止腹痛。得
白芍，治下痢。得桑白皮，
泻肺火。得白术，安胎。得米醋浸，炙七次为末，水服，治吐衄崩中下血。得酒炒为末服，
治灸疮出血。（一人灸至五壮，
血出不止如尿，手冷欲绝，服此即止。）配人参为末，治小儿惊啼。配白芷、细茶，治眉眶
痛。
酒炒，上行。生用，下行。猪胆汁炒，泻肝胆火。片芩泻肺胃上焦之火，子芩泻大肠下焦之
火。痘疹灌浆时，大肠无火，肺气虚弱，血虚胎动，皆禁用。黄芩、山栀、甘菊、知母、麦
冬、沙参、桑皮、地骨皮、
花粉、紫菀，皆制肺金之火。盖肺
本清肃之府，最畏者惟火。故气热而欲泄之，桑皮、地骨皮之类。邪火而欲泄之，山栀、黄
芩之类。金枯于火而欲泄之，沙参、麦冬之类。痰火而欲泄之，紫菀、花粉之类。木火侮金
而欲泄之，甘菊、黄芩之类。肾火烁金而欲泄之，知母、地骨皮之类。其余各经之火，皆能
侵犯肺金，务在各祛其火，不治肺而肺无不治，勿得专用黄芩以治肺火。
（胡黄连）畏菊花、玄参、白鲜皮。忌食猪肉，恐怕导致精气外泄。能解巴豆的毒性。
味极苦，性大寒。入足厥阴肝经、足少阴肾经的血分。能强力清除脏腑内的邪热，善于杀虫，搜剔深伏巢穴中的毒邪。消除积滞，治疗腹泻和痢疾，退除胎中蒸热，去除温疟，治疗小儿盗汗、惊风、疳积，以及成人伤寒咳嗽。与川黄连、朱砂配伍，治疗疳积发热引起的霍乱。与鹅胆、鸡蛋清调和涂抹，治疗痔疮肿痛剧烈难以忍受者。与栀子、猪胆汁配伍，治疗伤寒病愈后因劳累而复发的情况。与乌梅、灶心土配伍，治疗血痢。与黄连研为末，取一个黄瓜，去掉瓜瓤保留瓜盖，将药粉装入其中合定，外面用面糊包裹煨熟，去掉面糊，捣碎制成如绿豆大小的丸剂，根据患儿年龄大小用温水送服，治疗小儿黄疸。与猪脂、当归、甘草同用，治疗梅毒。用米泔水浸泡，柳木火焙干后使用。
旧根中间空心且干枯的称为片芩，又称枯芩。新根内部充实的称为子芩，又称条芩。
龙骨、山茱萸作为其引经药。畏丹砂、牡丹、藜芦。厌恶葱。
味苦，性寒。入手太阴肺经、手少阳三焦经、手阳明大肠经的气分。泻三焦的实火，祛除肌表的邪热，疏通气机郁滞，消除膈间痰饮，解除咽喉腥臭，化解斑疹，治疗疮疡，通利肠道闭塞，止住热痛，凉血安胎。与黄柏、白蔹、赤小豆配伍，治疗鼠瘘（淋巴结核）。与厚朴、川黄连配伍，止住腹痛。与白芍配伍，治疗痢疾。与桑白皮配伍，泻肺火。与白术配伍，安胎。用米醋浸泡，炙烤七次后研为末，用水送服，治疗吐血、衄血及崩漏下血。用酒炒制后研为末服用，治疗灸疮出血。（有一人艾灸至五壮，血流不止如尿状，手脚冰冷几乎断绝，服用此药即停止。）与人参研为末配伍，治疗小儿受惊啼哭。与白芷、细茶配伍，治疗眉眶疼痛。
酒炒后药性上行。生用则药性下行。猪胆汁炒制，可泻肝胆之火。片芩泻肺胃上焦的火邪，子芩泻大肠下焦的火邪。痘疹灌浆时期，若大肠无火，肺气虚弱，血虚胎动，均禁用。黄芩、山栀、甘菊、知母、麦冬、沙参、桑皮、地骨皮、花粉、紫菀，都能制约肺金之火。因为肺本是清肃之脏，最畏惧的就是火邪。所以气热想要宣泄的，用桑皮、地骨皮之类；邪火想要宣泄的，用山栀、黄芩之类；金被火灼干枯想要滋润的，用沙参、麦冬之类；痰火想要宣泄的，用紫菀、花粉之类；木火侮金想要宣泄的，用甘菊、黄芩之类；肾火烁金想要宣泄的，用知母、地骨皮之类。其余各经的火邪，都能侵犯肺金，务必分别祛除各经的火邪，不直接治肺而肺自然得治，不要专门只用黄芩来治肺火。
(Hu Huang Lian) Dislikes Chrysanthemi Flos (Juhua), Scrophulariae Radix (Xuanshen), and Dictamni Cortex (Baixianpi). Avoids pork, fearing it may cause leakage of essence. Resolves the toxicity of Crotonis Fructus (Badou).
Extremely bitter, extremely cold. Enters the blood level of the Foot Jueyin Liver Channel and Foot Shaoyin Kidney Channel. Strongly clears pathogenic heat from the Zang-Fu organs, excels at killing parasites, and searches out toxins hidden in deep nests. Eliminates food stagnation, treats diarrhea and dysentery,退了 fetal steaming heat, removes warm malaria, treats children's night sweats, convulsions, and malnutrition syndromes (Gan Ji), as well as adult Shanghan cough. Combined with Huanglian (Coptidis Rhizoma) and Cinnabaris (Zhusha), treats Gan-heat Huoluan. Mixed with goose bile and egg white for topical application, treats unbearable swelling and pain of hemorrhoids. Paired with Gardeniae Fructus (Zhizi) and pig bile, treats relapse due to overexertion after Shanghan. Paired with Mume Fructus (Wumei) and Zaoxia Tu (Furnace Earth), treats bloody dysentery. Ground into powder with Huanglian, take one cucumber, remove the pulp leaving the lid, insert the medicine, seal it, wrap in dough, and bake until cooked. Remove the dough, pound into pills the size of mung beans, and administer with warm water according to the child's age, treating pediatric jaundice. Used with pig fat, Danggui (Angelicae Sinensis Radix), and Gancao (Glycyrrhizae Radix et Rhizoma), treats meichuang (syphilis). Soaked in rice wash water, dried over willow wood fire.
Old roots that are hollow and withered are called Pian Qin (Slice Scutellariae Radix), also known as Ku Qin (Withered Scutellariae Radix). New roots that are solid inside are called Zi Qin (Seed Scutellariae Radix), also known as Tiao Qin (Strip Scutellariae Radix).
Longgu (Dragon Bone) and Corni Fructus (Shanzhuyu) act as its guides. Feared by Cinnabaris (Dansha), Paeoniae Rubra Radix (Mudanpi), and Veratri Rhizoma (Lilu). Dislikes Allii Fistulosi Bulbus (Cong).
Bitter, cold. Enters the Qi level of the Hand Taiyin Lung Channel, Hand Shaoyang Sanjiao Channel, and Hand Yangming Large Intestine Channel. Drains excess fire of the Triple Burner, dispels pathogenic heat from the muscle surface, promotes free flow of stagnant Qi, eliminates phlegm in the chest/diaphragm, resolves throat foulness, transforms macules and rashes, treats sores and ulcers, unblocks intestinal obstruction, stops painful heat, cools blood and calms the fetus. Combined with Huangbo (Phellodendri Cortex), Baijian (Ampelopsis Radix), and Adzuki Bean (Chixiaodou), treats Shulou (scrofula/lymphatic tuberculosis). Combined with Houpo (Magnoliae Officinalis Cortex) and Chuanlian (Coptidis Rhizoma), stops abdominal pain. Combined with Baishao (Paeoniae Radix Alba), treats dysentery. Combined with Sangbaipi (Mori Cortex), drains lung fire. Combined with Baizhu (Atractylodis Macrocephalae Rhizoma), calms the fetus. Soaked in rice vinegar, roasted seven times, ground into powder, taken with water, treats hematemesis, epistaxis, metrorrhagia, and bleeding from below. Roasted in wine, ground into powder, and taken, treats bleeding from moxibustion wounds. (One patient underwent five moxa cones, bleeding continuously like urine, hands and feet cold as if about to sever; taking this stopped the bleeding.) Paired with Renshen (Ginseng Radix et Rhizoma) as powder, treats infantile fright crying. Paired with Baizhi (Angelicae Dahuricae Radix) and Xiacha (Fine Tea), treats pain in the eyebrows and orbits.
Wine-fried, the action moves upward. Raw use, the action moves downward. Fried with pig bile, drains liver and gallbladder fire. Pian Qin drains upper jiao fire of the lungs and stomach; Zi Qin drains lower jiao fire of the large intestine. During the pustule-filling stage of smallpox/rash, if there is no fire in the large intestine, lung qi is deficient, blood deficiency causes fetal movement, all are contraindicated. Huangqin (Scutellariae Radix), Zhizi (Gardeniae Fructus), Ganju (Chrysanthemi Flos), Zhimu (Anemarrhenae Rhizoma), Maidong (Ophiopogonis Radix), Shashen (Glehniae Radix), Sangpi (Mori Cortex), Digupi (Lycii Cortex), Huafen (Trichosanthis Radix), Ziwan (Asteris Radix) all control the fire of Metal (Lung). The Lung is originally a pure and descending organ, most fearful of fire. Thus, for Qi heat wanting to be drained, use Sangpi, Digupi, etc. For pathogenic fire wanting to be drained, use Zhizi, Huangqin, etc. For Metal dried up by fire wanting to be moistened, use Shashen, Maidong, etc. For phlegm-fire wanting to be drained, use Ziwan, Huafen, etc. For Wood fire insulting Metal wanting to be drained, use Ganju, Huangqin, etc. For Kidney fire scorching Metal wanting to be drained, use Zhimu, Digupi, etc. Fire from other meridians can invade Lung Metal; one must eliminate the fire of each meridian separately. By not directly treating the Lung, the Lung is invariably treated; do not exclusively use Huangqin to treat Lung fire.