Single Herb Glossary
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) |
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.