Licorice Summary:

Licorice is one of the most popular herbs in the traditional Chinese medical system. It is a common addition to many formulas for its ability to amplify their actions. In western herbal medicine, this ability to improve the actions fo other herbs and pharmaceuticals in the body relate to its.....

Botanical Name

Glycyrrhiza glabra



Part Used


Herbal Actions:

  • Nootropic
  • Anodyne
  • Antispasmodic
  • Antinflammatory
  • Emolient
  • Estrogenic
  • Expectorant
  • Anti-ulcer

Specific Actions:

  • MAO-B inhibitor
  • Antiacetylcholinesterase
  • Serotonin reuptake inhibitor
  • Mimics aldosterone (cortisol potentiation)
licorice glycyrrhiza glabra


Liquid Extract (1:1)

2-6 ml/day (full spectrum)
1.5-4.5 ml/day (high glycyrrhizin extract)
1.2-4.8 ml/day (deglycyrrhizinized extract)

Dried Root

3-12 g/day

Flavouring Agent

Do not exceed 100 mg glycyrrhizin content

Order Some Now


  • Peptic and duodenal ulcers
  • Inflammation in the digestive tract
  • Respiratory tract inflammation
  • Low estrogen levels
  • Insulin resistance
  • Mouth ulcers
  • Viral hepatitis
  • Oral Lichen planus
  • Menopausal symptoms
  • Adrenal insufficiency
  • Corticosteroid dependency (to aid withdrawal symptomns after ceasing treatment)
  • Hyperkalaemia (from low aldosterone)
  • Rheumatoid arthritis
  • Protection against ulcer-forming medications like Aspirin
  • Diabetes mellitus complications (inhibition of aldose reductase)
  • Glaucoma (due to 11-beta-HSD1 inhibition)
  • Metabolic syndrome

Common Names:

  • Licorice
  • Licorice root
  • Sweet root
  • Gan Cao (China)
  • Kanzo (Japan)
  • Kamcho (Korean)
  • Subholzwurzel (Germany)
  • Lakritzenwurzel (Germany)
  • Reglisse
  • Bois Doux (France)
  • Liquirizia (Italy)
  • Lakrids (Danish)
  • Yashimadhu (Sanskrit)

Traditional Uses:

Liquorice is one of the fundamental herbs used in traditional Chinese, Ayurvedic, and Kampo medicine. 

In traditional Chinese medicine, licorice (known as Gan Cao), is used in two main forms; raw and prepared (usually by frying in honey).

Raw licorice is used to drain heat, reduce swelling, and detoxify. It is considered to be a muscle relaxant, alleviates pain, and harmonizes the harsh actions of other herbs in the formula. It is a common addition to a wide range of herbal formulas in traditional Chinese medicine for this reason. [11].

The saponin glycyrrhizin is intensly sweet. The Greek word Glycyrrhiza actually means sweet root.

Culpepper lists licorice as being useful for dry coughs, hoarseness of the throat, wheezing and shortness of breath.


    Botanical Description:

    Liquorice is part of the Fabaceae family of plants, which is more commonly known as the legume family. This includes such species as soy, peanuts, and astragalus. 

    It's a perennial herb, growing up to 150 cm tall. the rhizome is  thick, red-brown colored on the outside, and yellowish on the inside. 

    The flowers are zygomorphic. 

    Habitat Ecology, and Distribution:

    Liquorice's native range is from the Mediterranean to central and Southeast Asia. 

    Harvesting Collection, and Preparation:

    The root of the liquorice plant is the part used medicinally. 


    MAO-B inhibitory components are reported to be due to the
    licopyranocoumarin licocoumarone and glycyrrhisoflavone content of Glycyrhiza glabra [1]. 

    The triterpenoid saponin glycyrrhizin (2-6% [7]) and it's glycoside glycyrrhizic acid is both the cause of liquorices most dangerous side effects, and the active constituent for its biological activity. The main action of glycyrrhizin past its intense sweetness, involves the inhibition of the enzyme 11-beta-hydroxysteroid dehydrogenase, which is responsible for metabolising the stress hormone cortisol into the inactive form cortisone [4-6]. This is beneficial for conditions involving adrenal insufficiency, glaucoma, osteopenia, and metabolic syndrome, but can also cause undesired side effects including hypertension, and fluid retention. Because of this, deglycyrrhizinised versions of liquorice extracts are commercially available. 

    Glycyrrhetinicc acid is the aglycone of glycyrrhizic acid, which is considered the active constituent for liquorices anti-ulcer activity through mediation of prostaglandins in the mucous membrane [SOURCE]. 

    The root also contains a wide range of flavonoids (1%-1.5%) which are responsible for the yellow color of the root. Flavones (including liquiritin, rhamnoliquiritin), chalcones (including isoliquiritin), isoflavonoids (including glabridin, glabrone, and formonetin). Also included are coumarins, fatty acids (C2 to C16), phenolic compounds, and arabinogalactans. [8-10.  


    + Constituents Of Licorice

    Acetic-acid, Acetoin ,Acetol, Acetophenone, Alpha-terpineol Aluminum, Anethole, Apigenin, Ascorbic-acid, Asparagine, Benzaldehyde, Benzoic-acid, Benzyl-alcohol, Beta-sitosterol, Butan-1-ol-2-one, Butan-1-ol-3-one, Butane-2,3-diol, Butanoic-acid, Butylphthalate, Butyric-anhydride, Calcium, Camphor, Caproic-acid, Carvacrol, Choline, Chromium, Cobalt, Cumic-alcohol, Decane, Decanoic-acid, Difurfuryl-ether, Dihydro-5,5-dimethyl-2(3h)-furanone, Dimethyl-phenylethyl-alcohol, Docosane, Dodecane, Dodecanoic-acid, Eicosane, EO, Estragole, Estriol, Ethyl-linoleate, Ethyl- linolenate, Ethyl-palmitate, Ethyl-phenol ,Ethyl-phenylacetate, Eugenol, Fenchone Formononetin, Fructose, Furfural, Furfuryl-acetate, Furfuryl-alcohol, Furfuryl-butyrate, Furfuryl-formate,F urfuryl-propionate, Furyl-methyl-ketone, Gamma-butyrolactone, Gamma-heptalactone,G amma-hexalactone, Gamma-nonalactone, Gamma- octalactone, Geraniol, Glabrene, Glabric-acid, Glabridin, Glabrol, Glabrolide, Glabrone, Glucose, Glycocoumarin, Glycyrin, Glycyrol, Glycyrram, Glycyrrhetic-acid, Glycyrrhetinic-acid, Glycyrrhetol,G lycyrrhisoflavanone, Glycyrrhisoflavone, Glycyrrhizic-acid, Glycyrrhizin, Glyzaglabrin, Glyzarin, Guaiaco, Hederasaponin-c, Henicosane, Heptadecane ,Heptane-1,2-diol, Heptanoic-acid, Heranol, Herniarin, Hex-trans-3-en-ol, Hexadecane, Hexadecanoic-acid, Hexadecyl-acetate, Hexan-1-ol, Hexanoic-acid, Hexanol, Hexyl-formate, Hispaglabridin-a ,Hispaglabridin-b, Indole, Iron, Isobutyladipate, Isoglabrolide, soglycyrol, Isoliquiritin, Isomucronulatol, Isoneoliquiritin, Isoschaftoside, Isoviolanthin, Kumatakenin, Lavandolol, Licochalcone-a, Licochalcone-b, Licoflavonol, Licoisoflavanone, Licoisoflavones, Licoric-acid, Licuraside, Licuroside, Lignin, Linalool, Linalool-oxides, Liqcoumarin, Liquirazide, Liquiritic-acid, Liquiritigenin, Liquoric-acid, Magnesium, Maltose, Manganese, Methyl-ethyl-ketone, Methyl-hexa-decanoate, Methyl-hexanoate, Myrtenal, N-methyl-2-pyrrolidone, N-nonacosane, N- tetradecane, Neoliquiritin, Neosoliquiritin, Nonadecane, Nonanoic-acid, O-acetyl-salicylic-acid, O-cresol, O-methoxy-phenol, O-tolunitrile, Octacosan-1-ol, Octadecane, Octanoic-acid, P-cymenol, P-methoxy-phenol, Palmitic-acid, Pentadecane, Pentadecanoic-acid Pentan-1-ol, Pentanoic-acid, Phaseollinisoflavan, Phenethyl-alcohol, Phenol, Phenyl-acetaldehyde, Phenylpropionic-acid, Phosphorus, Propionic-acid, Pyrazole, Rhamnoisoliquiritin, Rhamno-liquiritin, Salicylic-acid, Schaftoside, Silicon, Stigmasterol, Sucrose, Sugar, Terpin-1-en-4-ol, Tetracosan-1-ol, Tetracosane, Tetradecanoic-acid, Tetramethyl-pyrazine, Thiamin, Thujone, Thymol, Tiglaldehyde, Tin, Tricosane, Tridecane, Tridecanoic-acid, Trimethyl-pyrazine, Umbelliferone, Undecane, Undecanoic-acid, Zinc

    Screen Shot 2017-10-28 at 2.01.19 PM.png

    Pharmacology and Medical Research:

    + Antiacetylcholinesterase

    Licorice powder (Glycyrhiza glabra) (aqueouse extract) (150 mg/kg), was shown to have a greater anti-acetylcholinesterase activity (25% inhibition), than nutmeg (Myristica fragrens) (15%) (5mg/kg), and Metrifonate (20% inhibition) (50 mg/kg) [3].

    + Effects On Cortisol

    Some of the components of Glycyrrhiza glabra such as glycyrrhetinic acid have been shown to inhibit 11β-hydroxysteroid dehydrogenase, which is the enzyme responsible for the breakdown and metabolism of cortisol. This activity was noted to sustain 2 weeks after treatment was ceased. The renin-aldosterone system remained low for 6 months following treatment. [12].

    11β-hydroxysteroid dehydrogenase bidirectionally converts inactive cortisone to cortisol, especially in tissues high in enzyme activity such as fatty tissue and the liver [13].

    This activity was noted to sustain 2 weeks after treatment was ceased. The renin-aldosterone system remained low for 6 months following treatment [12].

    + Ulcers

    The antiulcer effects of liquorice was shown to be due mainly to the glycyrrhetinic acid content of the root, which is the aglycone of triterpenoid saponin glycoside glycyrrhizic acid (Mills, S., & Bone, K. 1999, pg. 746-747). The mechanism of action is suggested to be through prostaglandin mediation. Specifically through the inhibition of 15-hydroxyprostaglandin dehydrogenase and delta-13-prostaglandin reductase (Wan & Gottfried., 1985). This causes an increase in the associated prostaglandins, which trigger an increase in increase of mucous secretion and cell proliferation in the stomach (Baker., 1994). This research was assisted by the creation of an identical semi-synthetic derivative of glycyrrhetinic acid and its glycoside precursor glycyrrhizic acid known commercially as Carbenoxolone (Mills & Bone, 1999).

    Additionally, liquorice extracts and semi-synthetic derivatives have been shown to produce anti pepsin activity in the stomach (Goso, Ogata, Ishihara, & Hotta., 1996), further improving the treatment of ulcers in the stomach.

    Liquorice was also shown to be effective in eradicating Helicobacter pylori in the treatment of peptic ulcer disease (PUD) (Momeni, Rahimian, Kiasi, Amiri, & Kheiri, 2014), though the study didn’t specify the extract used. The mechanisms of action are suggested to be through the flavonoid and polysaccharide fractions of Glycyrrhiza glabra extracts by inhibiting the adhesion of H. pylori to stomach tissue in vitro (human) (Wittschier, Faller, Beikler, Stratmann, & Hensel, 2006; Wittschier, Faller, & Hensel., 2009).

    Deglycyrrhizinated licorice was found ineffective in the treatment of ulcers in a randomised clinical trial, further suggesting that the anti-ulcerative effects of licorice is reliant on the glychyrhyzin component (and associated saccharides and aglycones) (Bardhan, Cumberland, Dixon, & Holdsworth. 1978).

    + Serotonin Reuptake Inhibition

    In a study investigating the effectiveness of licorice root extracts on serotinin reuptake inhibition as a way to analyse the possible antidepressant actions of the herb, serotonin reuptake was found to be effectively inhibited. The active constituents were found to be isoflavans and isoflavene constituents of licorice root. Glabridin inhibited serotonin re-uptake in a dose-dependent manner similarily to the human hormone, estradiol. [2].

    Other constituents preveiously thought to have SSRI activity such as isoflavone genistein and daidzein were instead found to be virtually inactive. [2].

    Discussing The Use Of Liquorice As An Adaptogen


    Avoid using with high blood pressure. The inhibition of 11-beta-hydroxysteroid dehydrogenase allows cortisol to build up, which increases blood pressure in both normotensive and hypertensive patients to the same degree. This can be dangerous for people already managing high blood pressure. 


    Avoid taking liquorice if on corticosteroids or diuretics.

    Drug Interactions:


    Still compiling research. 




    Justin Cooke

    The Sunlight Experiment

    Updated: April 2017

    Recent Blog Posts:


    1. Mazzio, E., Deiab, S., Park, K., & Soliman, K. F. A. (2013). High throughput screening to identify natural human monoamine oxidase B inhibitors. Phytotherapy Research, 27(6), 818-828.
    2. Ofir, R., Tamir, S., Khatib, S., & Vaya, J. (2003). Inhibition of serotonin re-uptake by licorice constituents. Journal of Molecular Neuroscience, 20(2), 135-40. doi:
    3. Sigurjonsdottir, H. A., Manhem, K., Axelson, M., & Wallerstedt, S. (2003). Subjects with essential hypertension are more sensitive to the inhibition of 11 β-HSD by liquorice. Journal of human hypertension, 17(2), 125-131.
    4. Heilmann, P., Heide, J., Hundertmark, S., & Schöneshöfer, M. (1999). Administration of glycyrrhetinic acid: significant correlation between serum levels and the cortisol/cortisone-ratio in serum and urine. Experimental and clinical endocrinology & diabetes, 107(06), 370-378. 
    5. Krähenbühl, S., Hasler, F. E. L. I. X., Frey, B. M., Frey, F. J., Brenneisen, R. U. D. O. L. F., & Krapf, R. (1994). Kinetics and dynamics of orally administered 18 beta-glycyrrhetinic acid in humans. The Journal of Clinical Endocrinology & Metabolism, 78(3), 581-585.
    6. Whorwood, C. B., Sheppard, M. C., & Stewart, P. M. (1993). Licorice inhibits 11 beta-hydroxysteroid dehydrogenase messenger ribonucleic acid levels and potentiates glucocorticoid hormone action. Endocrinology, 132(6), 2287-2292. Chicago    
    7. Sticher, O., & Soldati, F. (1978). Glycyrrhizinsaurebestimmung in Radix liquirtiae mit Hochleistungs Flussigkeitschromatographie (HPLC). Pharmaceutica acta Helvetiae.
    8. Wagner, H., & Bladt, S. (1996). Plant drug analysis: a thin layer chromatography atlas. Springer Science & Business Media.
    9. Bisset, N. G. (1994). Herbal drugs and phytopharmaceuticals: a handbook for practice on a scientific basis. Stuttgart: Medpharm Scientific Publishers xvi, 566p. ISBN 3887630254 En Originally published in German (1984).(EBBD, 190000550).
    10. Asl, M. N., & Hosseinzadeh, H. (2008). Review of pharmacological effects of Glycyrrhiza sp. and its bioactive compounds. Phytotherapy research, 22(6), 709-724.
    11. Dafang Zeng. (2003). Essentials Of Chinese Medicine Materia Medica. Bridge Pub. Group. [traditional medical text]. 
    12. Farese Jr, R. V., Biglieri, E. G., Shackleton, C. H., Irony, I., & Gomez-Fontes, R. (1991). Licorice-induced hypermineralocorticoidism. New England Journal of Medicine, 325(17), 1223-1227. [case study]. 
    13. Stewart, P. M., & Tomlinson, J. W. (2009). Selective Inhibitors of 11β-Hydroxysteroid Dehydrogenase Type 1 for Patients With Metabolic Syndrome. Diabetes, 58(1), 14-15.