Single Herb Glossary

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Gān Cǎo 甘草

Pharmaceutical name Glycyrrhizae Radix licorice root “sweet herb”
Category Tonify Qi
Key Properties Tonify SP Qi
Moisten LU
Moderate spasms/allergies
Harm other harsh herbs
Properties Sweet Neutral
Tropism All 12 chan;primarilyHT, LU, SP, ST
Actions & Indications 1) Tonifies SP & Augments Qi
2) Moistens LU & Stops Coughs
3) Moderates Spasms & Alleviates Pain
4) Clears Heat & Resolves Fire Toxicity
5) Used as an Antidote for a variety of Toxic substances, both internally and topically.
6) Moderates & Harmonizes characteristics of other herbs
Dosages 1.5-9g
When a large dosage is required, 15-30g can be used
Contraindications (TCM) Distention & Fullness of chest & abdomen or nausea/vomiting from overabundant dampness
Contraindications (Western) Large dosages or extended usage contraindicated with edema, kidney disorders, hypokalemia, hypertension, and congestive heart failure
Chemical Composition
Pharmacological Effects • Mineralocorticoid: extract of Gan Cao or its compounds (glycyrrhizin and glycyrrhetinic acid) have all demonstrated mineralocorticoid effects, leading to increased re-absorption of sodium and water and excretion of potassium; overdose or long-term ingestion may cause increase in edema and blood pressure
• Glucocorticoid: administration of glycyrrhizin and glycyrrhetinic acid clearly enhances overall duration of effect of cortisone, as demonstrated by various laboratory studies; proposed mechanisms of action vary among experts; some believe that enhanced cortisone effect is due to decreased metabolism by the liver, or increased plasma concentration caused by decreased protein binding
• Anti-inflammatory: glycyrrhizin and glycyrrhetinic acid have demonstrated marked anti-inflammatory effects; clinical applications include inflammation, edema, formation of granuloma, arthritis, and others; proposed mechanism of anti-inflammatory action includes decreased permeability of the blood vessels, antihistamine functions, and decreased sensitivity to stimuli; anti-inflammatory influence of glycyrrhizin and glycyrrhetinic acid is approximately 1/l0th that of cortisone
• Antiarrhythmic: extract of Zhi Gan Cao (Radix Glycyrrhizae Preparata) has shown marked effectiveness in treating arrhythmia induced by aconitine in rabbits
• Immunologic: administration may stimulate or inhibit phagocytic activity of macrophages in mice; under a stressful environment (cold, heat or hunger), stimulates immune system and increases phagocytic activities; in a normal environment, inhibits immune system
• Gastrointestinal: many components have proven to prevent and treat peptic ulcers; mechanisms of this action include inhibition of gastric acid secretion, binding and deactivation of gastric acid, and promotion of recovery from ulceration
• Antispasmodic: both water and alcohol extracts exert inhibitory influences on smooth muscle to stop spasms and cramps of intestines and uterus; antispasmodic effect enhanced when Bai Shao (Radix Paeoniae Alba) is added
• Antitoxin: glycyrrhizin, generally considered to be one of the main constituents of Gan Cao, has marked detoxifying effect to treat poisoning, including but not limited to drug poisoning (chloral hydrate, urethane, cocaine, picrotoxin, caffeine, pilocarpine, nicotine, barbiturates, mercury and lead), food poisoning (tetrodotoxin, snake and mushrooms), and others (enterotoxin, herbicides and pesticides); not effective in treating poisoning caused by atropine, morphine, and sulfonmethane; may increase toxicity of ephedrine; exact mechanism unclear, thought to be related to its regulatory effect on endocrine or hepatic systems; oral ingestion reduces absorption of toxins via direct binding, similar to activated charcoal; significantly reduces toxicity of Fu Zi (Radix Aconiti Lateralis Praeparata) when the two herbs are decocted together
• Hepatoprotective: studies in mice have shown that it increases amount of cytochrome p-450 in the liver, responsible for protective effect of the herb on the liver against chemical or tetrachloride-induced liver damage and liver cancer
• Antitussive and expectorant: administration associated with marked antitussive and expectorant effects in guinea pigs; antitussive effect thought to be related to its effect on CNS
• Analgesic: analgesic effect as demonstrated by studies in mice; analgesic effect enhanced by concurrent use of Bai Shao (Radix
• Paeoniae Alba)
• Antibiotic: inhibits growth of S. aureus, Mycobacterium tuberculosis, E. coli, amoebae and Trichomonas vaginalis
• Antihyperlipidemic: while glycyrrhizin has been shown to lower plasma cholesterol levels, Gan Cao has not demonstrated any preventative or treatment effect on atherosclerosis
Herb-Drug Interactions • Corticosteroids: use of Gan Cao may alter therapeutic effects of systemic corticosteroids; glycyrrhizin is a strong inhibitor of 11 β-hydroxysteroid dehydrogenase and may prolong biological half-life of systemic corticosteroids
• Digoxin: should be used with caution with cardiac glycosides, such as digoxin (Lanoxin), as potassium loss may increase toxicity of drug
• Drug overdose: speeds metabolism of drugs such as chloral hydrate, urethane, cocaine, picrotoxin, caffeine, pilocarpine, nicotine, and barbiturates, and treats overdose of these agents
• Incompatible with Gan Sui (Radix Kansui), Da Ji (Herba Sive Radix Cirsii Japonici), Yuan Hua (Flos Genkwa), Hai Zao (Sargassum)
Classical Formula(s)

Tiao Wei Cheng Qi Tang (Regulate the ST and order the Qi decoction) 調胃承氣湯 (调胃承气汤)

Wen Pi Tang (Warm the SP decoction) 溫脾湯

Xin Yi Qing Fei Yin (Magnolia Flower Drink to Clear the Lungs) 辛夷清肺飲

Yang He Tang(Balmy yang Decoction) 養和湯

Da Qin Jiao Tang (Major Large Gentian Decoction) 大秦艽湯

Dang Gui Nian Tong Tang (Tangkuei Decoction to Pry Out Pain) 當歸拈痛湯

Di Tan Tang (Scour Out Phlegm Decoction) 滌痰湯

Ding Chuan Tang (Arrest Wheezing Decoction) 定喘汤

Fang Ji Fu Ling Tang (Stephania and Poria Decoction) 防己茯苓湯

Fu Yuan Huo Xue Tang (Pao Shan Jia substituted with Wang Bu Liu Xing) (Revive Health by Invigorating the Blood Decoction) 復元活血湯

Gan Cao Gan Jiang Fu Ling Bai Zhu Tang (Licorice, Ginger, Poria and Atractylodis Macrocephalae Decoction) 甘草乾薑茯苓白朮湯

Gan Mai Da Zao Tang (Licorice, Wheat and Jujube Decoction) 甘麥大棗湯

Du Huo Ji Sheng Tang (Angelica Pubescens and Sang-Ji-Sheng Decoction)獨活寄生湯

Gui Zhi Shao Yao Zhi Mu Tang (Cinnamon Twig, Peony, and Anemarrhena Decoction) 桂枝芍藥知母湯

Huang Long Tang (Yellow Dragon Decoction) 黃龍湯

Jia Wei Wu Yao Tang (Augmented Lindera Decoction) 加味烏藥湯

Jiao Ai Tang (Ass-Hide Gelatin and Mugwort Decoction) 膠艾湯

Jing Jie Lian Qiao Tang (Schizonepeta and Forsythia Decoction) 荊芥連翹湯

Jiu Wei Qiang Huo Tang (Nine-Herb Decoction with Notopterygium) 九味羌活湯

Ju Pi Zhu Ru Tang (Tangerine Peel and Bamboo Shavings Decoction) 橘皮竹茹湯

Liang Ge San (Cool the Diaphragm powder) 涼膈散

Ling Gan Wu Wei Jiang Xin Tang (Poria, Licorice, Schisandra, Ginger & Asarium Decoction)苓甘五味薑辛湯

Long Dan Xie Gan Tang (gentian Decoction to Drain Liver) 龍膽瀉肝湯

Mai Men Dong Tang (Ophiopogonis Decoction) 麥門冬湯

Pu Ji Xiao Du Yin (Universal Benefit Drink to Eliminate toxin) 普濟消毒飲 (普济消毒饮)

Qian Jin Nei Tuo San (Powder to Support the Interior Worth a Thousand Gold Pieces) 千金内托散

Qing Shu Yi Qi Tang (Clear Summerheat and Augment the Qi Decoction) 清暑益氣湯

Qing Wen Bai Du Yin (Xi Jiao substituted with Shui Niu Jiao) (Clear Epidemics and Overcome Toxicity Drink 清瘟敗毒飲

Qing Xin Li Ge Tang (Clear the Heart and Enable the Diaphragm Decoction) 清心利膈湯

Qing Zao Jiu Fei Tang (Eliminate Dryness and Rescue the Lungs Decoctions) 清燥救肺湯

Ren Shen Bai Du San (Gingseng Powder to Over come Pathogenic Influences) 人參敗毒散

Sha Shen Mai Men Dong Tang (Glehnia and Ophiopogonis Decoction) 沙蔘麥門冬湯

Sang Ju Yin (Mulberry Leaf and Chrysanthemum Drink) 桑菊飲

Shi Wei Bai Du San (Ten-Ingredient Powder to Overcome Toxicity) (deleted ying pi) 十味敗毒散 (減櫻皮)

Si Miao Yong An Tang (Four-Valiant Decoction for Well-Being)四妙勇安湯

Suan Zao Ren Tang (Sour Jujube Decoction) 酸棗仁湯 (酸枣仁汤)

Tuo Li Xiao Du Yin (Support the Interior and Eliminate Toxin Drink) 托裡消毒飲

Wen Jing Tang (Flow-Warming Decoction) 溫經湯

Wu Lin San (Powder for Five Types of Painful Urinary Dribbling) 五淋散

Xue Fu Zhu Yu Tang (Drive Out Stasis from the Mansion of Blood Decoction) 血府逐瘀湯

Yi Qi Cong Ming Tang (Augment the Qi and Increase Acuity Decoction) 益氣聰明湯

Yin Qiao San (Honeysuckle and Forsythia Powder) 銀翹散 (银翘散)

Zhen Gan Xi Feng Tang (Sedate the Liver and Extinquish Wind Decoction) 鎮肝熄風湯

Bai He Gu Jin Tang (Lily bulb decoction to preserve the metal) 百合固金湯

Bai Tou Weng Jia Gan Cao E Jiao Tang (Pulsatilla Decoction plus Licorice and Ass-Hide Gelatin) 白頭翁加甘草阿膠湯

Bai Zi Yang Xin Tang (Arborvitae See Pill to Nourish the HT) 柏子養心湯

Ban Xia Bai Zhu Tian Ma Tang(Pinellia, White Atractylodes & Gastrodia Decoction) 半夏白朮天麻湯

Bao Chan Wu You Fang (Worry-Free Formula to Protect Birth) 保產無憂方

Bu Dai Wan(Cloth Sack Pill) 布袋丸

Bu Huan Jin Zheng Qi San (Rectify the Qi Powder Worth More than Gold) 不換金正氣散

Chai Ge Jie Ji Tang (Buplerum and Kudzu Decoction to Release the Muscle Layer) 柴葛解肌汤

Chai Hu Gui Zhi Tang (Bupleurum and Cinnamon Twig Decoction) 柴胡桂枝湯

Da Huang Zhe Chong Wan (Rhubarb and Ground Beetle Pill) (delete gan qi, qi cao, meng chong) 大黃蛰虫丸 (減乾漆,蠐螬,虻虫)

Da Yuan Yin (Reach the Source Drink) 達原飲

Dao Chi San (Guide Out the Red Powder) 導赤散

Fang Feng Tong Sheng San (Saposhnikovia powder that sagely unblocks) 防風通聖散

Feng Yin Tang (Wind-Drawing Decoction) (deleted bai shi zhi) 風引湯 (減白石脂)

Gui Zhi Jia Long Gu Mu Li Tang (Cinnamon Twig Decoction plus Dragon Bone and Oyster Shell) 桂枝加龍骨牡蠣湯

Hai Zao Yu Hu Tang (Sargassum decoction for the Jade Flask) 海藻玉壺湯

Hao Qin Qing Dan Tang Sweet Wormwood and Scutellaria Decoction to Clear Gallbladder) 蒿芩清膽湯

Hua Ban Tang (Transform Maculae Decoction) (deleted jing mi, replaced xi jiao with shui niu jiao) 化斑湯 (減粳米) (犀角用水牛角代替)

Huang Tu Tang (delete Zao Xin Tu) (Yellow Earth Decoction) 黃土湯(減灶心土)

Jian Pi Wan (Strenghten the Spleen Pill) 健脾丸

Shi Liu Wei Liu Qi Yin (Sixteen Ingredient Drink for Qi Flow) 十六味流氣飲

Ling Jiao Gou Teng Tang (Ling Yang Jiao substituted with Shui Niu Jiao (Antelope Horn and Unicaria Decoction)羚角鉤藤湯 (羚角钩藤汤)

Qing Gu San (Cool the Bones Powder) 清骨散

Su Zi Jiang Qi Tang (Perilla Fruit Decoction for Directing Qi down) 蘇子降氣湯 (苏子降气汤)

Wan Dai Tang (End Discharge Decoction) 完帶湯 (完带汤)

Wu Ji San (Five-accumula-tion powder) 五积散

Xian Fang Huo Ming Yin (Immortals Formula for Sustaining Life) 仙方活命飲

Xiao Xu Ming Tang (Minor Prolong Life Decoction) 小續命湯

Xie Huang San (Drain the Yellow Powder) 瀉黃散

Xing Su San (Apricot Kernel and Perilla Leaf Powder) 杏蘇散 (杏苏散)

Yang Yin Qing Fei Tang (Nourish the Yin and Clear the Lungs Decoction) 養陰清肺湯

Yu Quan Wan (Jade Spring Pill) 玉泉丸

Zai Zao San (Renewal Powder) 再造散

Zhi Sou San (Stop Coughing Powder) 止嗽散

Xiao Feng San (Eliminate Wind Powder) 消風散


This information is a reference tool for Chinese herbal studies. It is not intended to replace professional medical advice. Please consult a primary health professional if you require health advisory.