气平。味辛。有毒。主伤寒寒热心下坚。胸胀咳逆头眩。咽喉肿痛。肠鸣。下气。
止汗。（汤浸去涎净姜汁拌焙）
半夏气平。禀天秋燥之金气。入手太阴肺经。味辛有毒。得地西方酷烈之金味。入足阳
明胃
经、手阳明大肠经。气平味升。阳也。主伤寒寒热心下坚者。心下脾肺之区。太阴经行之地
也。病伤寒寒热而心下坚硬。湿痰在太阴也。半夏辛平。消痰去湿。所以主之。胸者肺之部
也。胀者气逆也。半夏辛平。辛则能开。平则能降。所以主之也。咳逆头眩者。痰在肺。则
气不下降。气逆而头眩晕也。东垣曰。太阴头痛。必有痰也。半夏辛平消痰。所以主之。咽
喉太阴经行之地。火结则肿痛。其主之者。辛能散结。平可下气。气下则火降也。肠鸣者。
大肠受湿。则肠中切痛。而鸣濯濯也。辛平燥湿。故主肠鸣。下气者。半夏入肺。肺平则气
下也。阳明之气本下行。上逆则汗自出矣。平能降气。所以止汗也。
制 方:
半夏同黄连、栝蒌实。名小陷胸汤。治心下坚。同甘草、防风、生姜。治痰厥中风。同
神曲
、南星、白术、枳实、姜汁。治风痰湿痰。同甘草。治风痰喘急。同黄芩、姜汁。治上焦热
痰。同白芍、甘草、黄芩。治身热吐泻。同瓜仁。治肺热咳。同陈皮。治痰饮。同白茯。治
水饮。同人参。治反胃。同白茯、甘草丸。名消暑丸。治伏暑。同人参、白茯、白术、甘草
、陈皮。名六君子汤。治脾湿生痰。不思饮食。
气味平和。味道辛。有毒。主治伤寒引起的寒热交替、心下痞硬、胸部胀满、咳嗽气逆、头晕目眩、咽喉肿痛、肠鸣音亢进。具有降气、止汗的功效。（制作方法是：用汤水浸泡，去除涎沫，洗净后用姜汁拌匀焙干）
半夏气味平和，禀受了秋季燥金的天气，归入手太阴肺经。味道辛且有毒，获得了西方酷烈之金的味道，归入足阳明胃经和手阳明大肠经。其气平而味升，属于阳。主治伤寒寒热伴有心下坚硬的症状，心下是脾肺所在的区域，也是太阴经循行的部位。患伤寒出现寒热且心下坚硬，是因为湿痰停滞在太阴经。半夏辛平，能消除痰湿，所以主治此症。胸是肺的分区，胀是气机逆乱的表现。半夏辛平，辛味能开散，平性能下降，所以主治此症。咳嗽气逆、头晕目眩，是因为痰在肺中，导致气不能下降，气机上逆引起头部眩晕。李东垣说：太阴头痛，必定有痰。半夏辛平能消痰，所以主治此症。咽喉是太阴经循行的部位，火邪郁结则导致肿痛。半夏之所以能主治，是因为辛味能散结，平性能下气，气降则火随之而降。肠鸣，是因为大肠受湿邪侵袭，导致肠中剧烈疼痛，发出濯濯的水声。半夏辛平能燥湿，所以主治肠鸣。所谓“下气”，是因为半夏入肺经，肺气平和则气机下行。阳明经的气本应下行，如果上逆则会导致自汗。半夏的平性能降气，所以能止汗。
制方方法：
半夏与黄连、瓜蒌实同用，名为小陷胸汤，治疗心下痞硬。与甘草、防风、生姜同用，治疗痰厥中风。与神曲、天南星、白术、枳实、姜汁同用，治疗风痰和湿痰。与甘草同用，治疗风痰引起的喘急。与黄芩、姜汁同用，治疗上焦的热痰。与白芍、甘草、黄芩同用，治疗身体发热伴呕吐腹泻。与瓜仁（冬瓜子）同用，治疗肺热咳嗽。与陈皮同用，治疗痰饮。与茯苓同用，治疗水饮。与人参同用，治疗反胃。与茯苓、甘草制成丸剂，名为消暑丸，治疗伏暑。与人参、茯苓、白术、甘草、陈皮同用，名为六君子汤，治疗脾虚湿盛生痰、食欲不振。
Nature is neutral. Flavor is acrid. It is toxic. It primarily treats chills and fever associated with Shanghan (Cold Damage), hardness in the epigastrium, chest distension, cough with counterflow qi, dizziness, sore throat and swelling, and borborygmus. It directs qi downward and stops sweating. (Preparation: Soak in decoction, remove saliva/mucus, wash clean, mix with ginger juice, and bake.)
Banxia (Pinelliae Rhizoma) has a neutral nature, inheriting the dry metal energy of autumn, entering the Hand-Taiyin Lung Meridian. Its flavor is acrid and it is toxic, acquiring the intense metal flavor of the west, entering the Foot-Yangming Stomach Meridian and the Hand-Yangming Large Intestine Meridian. Its nature is neutral and its flavor ascends; it belongs to Yang. It treats chills and fever with hardness in the epigastrium because the epigastrium is the region of the Spleen and Lung, where the Taiyin Meridian travels. When one contracts Shanghan resulting in chills, fever, and hardness in the epigastrium, it is due to damp-phlegm stagnating in the Taiyin. Banxia is acrid and neutral, eliminating phlegm and drying dampness, thus treating this condition. The chest is the domain of the Lung; distension indicates counterflow of qi. Banxia is acrid and neutral; acridness can disperse, and neutrality can descend, thus treating this condition. Cough with counterflow qi and dizziness occur because phlegm in the Lung prevents qi from descending; the counterflowing qi causes dizziness. Li Dongyuan stated: "Taiyin headache must involve phlegm." Banxia is acrid and neutral, eliminating phlegm, thus treating this condition. The throat is the pathway of the Taiyin Meridian; fire accumulation causes swelling and pain. Banxia treats this because acridness can dissipate nodules, and neutrality can direct qi downward; when qi descends, fire also descends. Borborygmus occurs because the Large Intestine is affected by dampness, causing cutting pain in the intestines and gurgling sounds. Banxia is acrid and neutral, drying dampness, thus treating borborygmus. "Directing qi downward" refers to Banxia entering the Lung meridian; when Lung qi is balanced, qi descends. The Qi of the Yangming Meridian naturally flows downward; if it counterflows upward, spontaneous sweating occurs. Banxia's neutrality can descend qi, thus stopping sweating.
Formulation Methods:
Banxia combined with Huanglian (Coptidis Rhizoma) and Gualou Shi (Trichosanthis Fructus), named Xiaoxianxiong Tang (Minor Intrapectoral Decoction), treats hardness in the epigastrium. Combined with Gancao (Glycyrrhizae Radix et Rhizoma), Fangfeng (Saposhnikoviae Radix), and Shengjiang (Zingiberis Rhizoma Recens), it treats stroke due to phlegm-jue. Combined with Shenqu (Massa Medicata Fermentata), Nanting (Arisaracae Rhizoma), Baizhu (Atractylodis Macrocephalae Rhizoma), Zhishi (Aurantii Fructus Immaturus), and Jiangzhi (Zingiberis Rhizoma Recens Juice), it treats wind-phlegm and damp-phlegm. Combined with Gancao, it treats wheezing and urgency due to wind-phlegm. Combined with Huangqin (Scutellariae Radix) and Jiangzhi, it treats upper jiao heat-phlegm. Combined with Baishao (Paeoniae Radix Alba), Gancao, and Huangqin, it treats body heat with vomiting and diarrhea. Combined with Gua Ren (Benincasae Semen), it treats lung-heat cough. Combined with Chenpi (Citri Reticulatae Pericarpium), it treats phlegm-fluid retention. Combined with Fuling (Poria), it treats water-fluid retention. Combined with Renshen (Ginseng Radix et Rhizoma), it treats regurgitation. Combined with Fuling and Gancao as pills, named Xiaoshu Wan (Summerheat-Dispelling Pill), treats latent summerheat. Combined with Renshen, Fuling, Baizhu, Gancao, and Chenpi, named Liujunzi Tang (Six Gentlemen Decoction), treats phlegm generated by spleen-dampness and loss of appetite.