五脏六腑。皆秉气于胃。五脏六腑之气。亦皆发见于胃。口者。胃之门户。故五脏六腑之气。皆见于此。口苦
是胆热。小柴胡汤。加黄连治之。口甘是脾热。甲己化土汤。加天花粉茵陈蒿炒栀子茯苓枳壳浓朴黄芩
石膏治之。口酸是湿热。观炎天羹肉过夜则酸。便知酸是湿热所化。葛根黄连黄芩汤。加防己茵陈木通
滑石花粉云苓治之。或苍术黄柏黄连吴茱萸亦治之。口咸是脾湿。润下作咸。脾不化水。故咸也。二陈汤。
加旋复花藿香白芍檀香吴茱萸治之。胃苓汤亦治之。或六味地黄汤。加旋复花牛膝白前根。从肾中化
水。纳之下行。以隔治之。口淡是胃虚。六君子汤。随寒热加减治之。口涩是风热。通圣散。去芒硝大黄治之。
口麻是血虚。圣愈汤。加薄荷治之。口臭是食积之火。平胃散。加山楂神曲麦芽黄芩石膏治之。口中糜烂。
是膀胱遗热于小肠。热气不得下泄。故糜及于口。导赤散。加天花粉天门冬麦门冬金银花灯心车前子
栀子治之。喉腥是肺火痰滞。泻白散。合甘桔汤。再加射干马兜铃黄芩杏仁川贝母天冬麦冬百合栝蒌
霜治之。总而论之。口乃胃之门户。总以治胃为主。宜分舌热。用甘露饮平胃散。加减治之。
舌为心之苗。而居口中。脏腑之气。发见于口者。多着于舌。故即舌苔。可以诊知脏腑诸病。伤寒邪在表者。
舌无苔。在半表半里者。舌乃有苔。入里则苔结矣。故凡有苔。皆系内证。苔白为湿热。小柴胡汤。加花粉石
膏滑石木通治之。苔黄为燥热。犀角地黄汤。加知母石膏天花粉大黄枳壳治之。黑苔芒刺为实热。大承
气汤治之。若苔黑而舌滑润者。乃水极似火。真寒假热之证。四逆汤。加猪胆汁人尿葱白治之。血家虚火。
又宜地黄汤。加肉桂牛膝五味子龙骨。以引导之。
又凡舌肿舌裂。痛疮等证。均是心脾火毒。泻心汤治之。大清凉散亦治之。若舌根木强。或舌短缩者。皆是
少阴经风邪内动。阴火上腾之候。地黄饮子。加羚羊角治之。
上所论口舌诸证。血家间亦有之。要宜以血证为主。参以上各法。斯为本末兼权之术。
五脏六腑，都禀受胃气。五脏六腑的气机，也都显露在胃。口，是胃的门户，所以五脏六腑的气机，都会表现在这里。
口苦，是胆热所致，用小柴胡汤（小柴胡汤），加黄连治疗。
口甘，是脾热所致，用甲己化土汤（甲己化土汤），加天花粉、茵陈蒿、炒栀子、茯苓、枳壳、浓朴、黄芩、石膏治疗。
口酸，是湿热所致，看夏天饭菜过夜会变酸，就知道酸味是由湿热转化而来，用葛根黄连黄芩汤（葛根芩连汤），加防己、茵陈、木通、滑石、花粉、云苓治疗；或者用苍术、黄柏、黄连、吴茱萸也能治疗。
口咸，是脾湿所致，“润下作咸”，脾不能运化水湿，所以出现咸味，用二陈汤（二陈汤），加旋复花、藿香、白芍、檀香、吴茱萸治疗；胃苓汤（平胃散合五苓散）也能治疗；或者用六味地黄汤（六味地黄丸），加旋复花、牛膝、白前根，从肾中化水，引导下行，以“隔治法”治疗。
口淡，是胃虚所致，用六君子汤（六君子汤），根据寒热情况加减治疗。
口涩，是风热所致，用防风通圣散（防风通圣散），去掉芒硝、大黄治疗。
口麻，是血虚所致，用圣愈汤（圣愈汤），加薄荷治疗。
口臭，是食积化火所致，用平胃散（平胃散），加山楂、神曲、麦芽、黄芩、石膏治疗。
口中糜烂，是膀胱余热遗留给小肠，热气不能向下排泄，所以腐蚀波及到口腔，用导赤散（导赤散），加天花粉、天门冬、麦门冬、金银花、灯心草、车前子、栀子治疗。
喉部有腥味，是肺火痰滞所致，用泻白散（泻白散），合甘桔汤（甘草桔梗汤），再加射干、马兜铃、黄芩、杏仁、川贝母、天冬、麦冬、百合、栝蒌霜治疗。
总而言之，口是胃的门户，总体以治疗胃为主，适宜区分舌苔之热，用甘露饮（甘露饮）和平胃散，加减治疗。
舌是心的苗窍，位于口中，脏腑之气显露在口的，多附着于舌，所以通过观察舌苔，可以诊断脏腑的各种疾病。伤寒邪气在表时，舌上没有苔；在半表半里时，舌上才有苔；进入里证则舌苔凝结。所以凡是有舌苔的，都属于内证。
舌苔白，为湿热，用小柴胡汤，加花粉、石膏、滑石、木通治疗。
舌苔黄，为燥热，用犀角地黄汤（犀角地黄汤），加知母、石膏、天花粉、大黄、枳壳治疗。
黑苔且有芒刺，为实热，用大承气汤（大承气汤）治疗。如果舌苔黑而舌面滑润，这是水极似火，真寒假热的证候，用四逆汤（四逆汤），加猪胆汁、人尿、葱白治疗。失血患者因虚火，又宜用地黄汤，加肉桂、牛膝、五味子、龙骨，以引火归元。
另外，凡是舌肿、舌裂、痛疮等证候，都是心脾火毒，用泻心汤（泻心汤）治疗，大清凉散也能治疗。如果舌根僵硬强直，或舌头短缩，都是少阴经风邪内动，阴火上腾的表现，用地黄饮子（地黄饮子），加羚羊角治疗。
上面论述的口舌各种证候，失血患者中间也有发生，但应当以血证为主，参考以上各法，这才是标本兼顾的方法。
The Zang and Fu organs all derive their Qi from the Stomach. The Qi of the Zang and Fu organs also manifests in the Stomach. The mouth is the gateway of the Stomach; therefore, the Qi of the Zang and Fu organs all manifest here.
Bitter taste in the mouth indicates Gallbladder Heat (Dan Re). It is treated with Xiao Chai Hu Tang (Minor Bupleurum Decoction) plus Huang Lian (Coptidis Rhizoma).
Sweet taste in the mouth indicates Spleen Heat (Pi Re). It is treated with Jia Ji Hua Tu Tang (Jia Ji Transforming Earth Decoction) plus Tian Hua Fen (Trichosanthis Radix), Yin Chen Hao (Artemisiae Scopariae Herba), fried Zhi Zi (Gardeniae Fructus), Fu Ling (Poria), Zhi Ke (Aurantii Fructus), Hou Po (Magnoliae Officinalis Cortex), Huang Qin (Scutellariae Radix), and Shi Gao (Gypsum Fibrosum).
Sour taste in the mouth indicates Damp-Heat (Shi Re). Observing that soup and meat turn sour overnight in summer reveals that sourness is transformed by Damp-Heat. It is treated with Ge Gen Huang Lian Huang Qin Tang (Kudzu, Coptis, and Scutellaria Decoction) plus Fang Ji (Stephaniae Tetrandrae Radix), Yin Chen, Mu Tong (Akebiae Caulis), Hua Shi (Talcum), Hua Fen, and Yun Ling. Alternatively, Cang Zhu (Atractylodis Rhizoma), Huang Bai (Phellodendri Cortex), Huang Lian, and Wu Zhu Yu (Evodiae Fructus) may also be used.
Salty taste in the mouth indicates Spleen Dampness (Pi Shi). "Moisture descending produces salt." Since the Spleen fails to transform water, saltiness appears. It is treated with Er Chen Tang (Two-Cured Decoction) plus Xuan Fu Hua (Inulae Flos), Huo Xiang (Agastaches Herba), Bai Shao (Paeoniae Radix Alba), Tan Xiang (Santalum Album Lignum), and Wu Zhu Yu. Wei Ling Tang (Stomach-Ling Decoction, a combination of Ping Wei San and Wu Ling San) is also effective. Alternatively, Liu Wei Di Huang Tang (Six-Ingredient Rehmannia Decoction) plus Xuan Fu Hua, Niu Xi (Achyranthis Bidentatae Radix), and Bai Qian Gen (Cynanchi Stauntonii Radix) can be used to transform water in the Kidney and guide it downward, employing the "remote treatment" method.
Insipid taste in the mouth indicates Stomach Deficiency (Wei Xu). It is treated with Liu Jun Zi Tang (Six-Gentlemen Decoction), modified according to Cold or Heat.
Astringent taste in the mouth indicates Wind-Heat (Feng Re). It is treated with Feng Wang Tong Sheng San (Wind-Blocking Universal Salvation Powder), removing Mang Xiao (Natrii Sulfas) and Da Huang (Rhei Radix et Rhizoma).
Numbness in the mouth indicates Blood Deficiency (Xue Xu). It is treated with Sheng Yu Tang (Holy Rescue Decoction) plus Bo He (Menthae Haplocalycis Herba).
Bad breath indicates Fire from Food Retention (Shi Ji Zhi Huo). It is treated with Ping Wei San (Peaceful Stomach Powder) plus Shan Zha (Crataegi Fructus), Shen Qu (Massa Medicata Fermentata), Mai Ya (Hordei Fructus Germinatus), Huang Qin, and Shi Gao.
Ulceration in the mouth indicates residual Heat from the Bladder transferring to the Small Intestine. The Heat cannot descend and discharge, thus eroding the mouth. It is treated with Dao Chi San (Guide Out Redness Powder) plus Tian Hua Fen, Tian Dong (Asparagi Radix), Mai Dong (Ophiopogonis Radix), Jin Yin Hua (Lonicerae Japonicae Flos), Deng Xin Cao (Junci Medullia), Che Qian Zi (Plantaginis Semen), and Zhi Zi.
Fishy odor in the throat indicates Lung Fire with Phlegm Stagnation (Fei Huo Tan Zhi). It is treated by combining Xie Bai San (Drain White Powder) with Gan Jie Tang (Licorice and Platycodon Decoction), plus She Ye (Belamcandae Rhizoma), Ma Dou Ling (Aristolochiae Manshuriensis Fructus), Huang Qin, Xing Ren (Pruni Semen), Chuan Bei Mu (Fritillariae Cirrhosae Bulbus), Tian Dong, Mai Dong, Bai He (Lilii Bulbus), and Gua Lou Shuang (Benincasae Exocarpium Pulveratum).
In summary, the mouth is the gateway of the Stomach; treatment primarily focuses on the Stomach. One should differentiate tongue heat, using Gan Lu Yin (Sweet Dew Drink) and Ping Wei San, modified as needed.
The tongue is the sprout of the Heart and resides in the mouth. The Qi of the Zang and Fu organs manifesting in the mouth often attaches to the tongue. Therefore, by observing the tongue coating, one can diagnose various diseases of the Zang and Fu organs. When Sha Yang pathogenic factors are in the Exterior, there is no tongue coating. When they are in the Half-Exterior/Half-Interior, a tongue coating appears. When they enter the Interior, the coating becomes thick and adherent. Thus, any tongue coating indicates an Internal Syndrome.
White coating indicates Damp-Heat, treated with Xiao Chai Hu Tang plus Hua Fen, Shi Gao, Hua Shi, and Mu Tong.
Yellow coating indicates Dry-Heat, treated with Xi Jiao Di Huang Tang (Rhino Horn and Rehmannia Decoction) plus Zhi Mu (Anemarrhenae Rhizoma), Shi Gao, Tian Hua Fen, Da Huang, and Zhi Ke.
Black coating with prickles indicates Excess Heat, treated with Da Cheng Qi Tang (Major Order the Qi Decoction). If the black coating is accompanied by a slippery and moist tongue surface, it indicates Water Extremity resembling Fire, a pattern of True Cold and False Heat. It is treated with Si Ni Tang (Four Counterflow Decoction) plus Zhu Dan Zhi (Porci Bile), Ren Niao (Human Urine), and Cong Bai (Allii Fistulosi Bulbus). For patients with blood disorders suffering from Deficient Fire, Di Huang Tang (Rehmannia Decoction) plus Rou Gui (Cinnamomi Cortex), Niu Xi, Wu Wei Zi (Schisandrae Chinensis Fructus), and Long Gu (Fossilia Ossis Mastodi) should be used to guide the fire back to its source.
Furthermore, conditions such as swollen tongue, cracked tongue, painful sores, etc., are all due to Heart and Spleen Fire-Toxin. They are treated with Xie Xin Tang (Drain the Heart Decoction) or Da Qing Liang San (Great Cooling and Clearing Powder). If the base of the tongue is stiff or the tongue is short and retracted, it indicates internal stirring of Wind Pathogen in the Shao Yin Meridian and rising of Deficient Fire. It is treated with Di Huang Yin Zi (Rehmannia Elixir) plus Ling Yang Jiao (Saigae Tataricae Cornu).
The aforementioned oral and lingual syndromes may also occur in patients with blood disorders. However, treatment should prioritize the blood disorder, referencing the above methods. This constitutes a strategy that addresses both root and branch.