Gan Cao

Glycyrrhizae Radix, Licorice

Dosage

1.5-9g.

Toxicity

LD50: 2.52g/kg (mice/water-based extract/abdominal injection); LD100: 3.6g/kg (mice/water-based extract/hypodermic injection). (1)

Chemical Composition

Glycyrrhizin; 18(-glycyrrhetic acid; Glucuronic acid; Glycyrrhizic acid; Uralsaponin A, B; Liquiritigenin; Liquiritin; Isoliquiritfigenin; Isoliquiritin; Neoliquiritin; Neoisoliquiritin; Licoricidin; Licoricone; Formononetin; 5-O-methyllicoricidin; Vicenin II; Ononin; Isolicoflavonol; Licuraside; Apioisoliquiritin; Glycycoumarine; Glycyrol; Isoglycyrol; Glycyrin; Neoglycyrol; Licopyranocoumarin; Licocoumarone; Licobenzofuran; Liconeolignan; (-sitosterol; N-tricoxane; N-hexacosane; N-heptacosane; Glucan GBW; Narcissin; Nicotiflorin; Rutin; Isoquercitrin; Astragalin; Uralenol; Neouralenol; Uralenin; Uralene; Quercetin; Uralennoeoside; Scopoletin; Lupiwighteone; Sigmoidin B; Gancaonin A-E, L-V; Glycyrrigan UA, UB, UC; Polysacchaside GR-2IIa, GR-2IIb, GR-2IIc; Quercetin-3,3'-dimethylether; Uralenol-3-methylether; Liquiritigenin-7-4-'-diglucoside; 5,6,7,8-tetrahydro-4-methylquinoline; 5,6,7,8-tetrahydro-2,4-dimethylquinoline; 3-methyl-6,7,8-trihydropyrrolo(1,2,-a)pyrimidin-3-one; Isoliquiritfigenin-4-apiofuranosyl(1→2)glucopyranoside; Licoricesaponine A3, B2, C2, D3, E2, F3, G2, H2, J2, K2; Liquiritigenin-4'-apiofuranosyl(1→2); glucopyranoside, apioliquiritin. (2)

Precautions

Reported adverse effects: hypocalcemia, asthma, agalactia, rashes, impotence, hypertension, infantile diarrhea, heart and renal damages, etc. (3) , (4) , (5) , (6) , (7) , (8) , (9) , (10)

Gan Cao is incompatible with the following products: digitalis, digoxin, tolbutamide, phenformin, insulin, glybenzcyclamide, aspirin, sodium salicylate, tannic acid, dihydrochlorothiazide, quinine, reserpine, ephedrine, pepsase, and berberine. (11)

Pharmacology

Anti-viral effect

Glycyrrhizin, an active component of Gan Cao, inhibits the proliferation of AIDS virus. In-vitro experiments show that Gan Cao polysaccharides inhibit vesicular stomatitis virus, adenovirus II, herpes simplex virus I, and vaccinia virus. (12)

Anti-bacterial effect

Used in combination with Huang Lian and Huang Qin, Gan Cao enhances the combination's inhibitory effect on bacteria. (13) , (14) At a certain concentration, Gan Cao alone has an inhibitory effect on Helicobacterium. (15)

Dilating trachea

Gan Cao can inhibit the tracheal constriction induced by histamine and acetylcholine. (16)

Anti-aging effect

Administered to senile rats, water-based decoction of Gan Cao can increase the activity of superoxide dismutase, lower the lactoperoxidase level, and decrease the activity of MAO-B (p

Effects on the digestive system

Administered to mice at the dosage of 6g/kg, Gan Cao can inhibit immersion-induced stress ulcer and hydrochloride acid-induced ulcer. Administered to rats at the dosage of 1.2g/kg, Gan Cao can increase the bile volume. (17) , (18)

Effects on the cardiovascular system

Gan Cao can improve the heart function, decrease myocardial oxygen consumption, and improve the general condition of blood vessels. (19)

Anti-arrhythmia effect

Gan Cao can counteract aconitine-induced arrhythmia. (20)

Anti-oxidation effect

Gan Cao extract inhibits the reductive metabolism of fluothane, decreasing the intermediate products. Gan Cao also inhibits lipid peroxidation, decreasing the occurrence of fluothane-caused hepatitis. (21) , (22)

References

  1. Editorial Committee of Chinese Materia Medica. State Drug Administration of China. Chinese Materia Medica. Shanghai: Science and Technology Press; 1998.
  2. Editorial Committee of Chinese Materia Medica. State Drug Administration of China. Chinese Materia Medica. Shanghai: Science and Technology Press; 1998.
  3. Li Cui Lan, et al. Journal of Chinese Materia Medica. 1996;37(9):570.
  4. WuChang Fu, et al. Jiangsu Journal of Traditional Chinese Medicine. 1986;7(9):17.
  5. Zhou Jian Xiong. Traditional Chinese Medicine Bulletin. 1986;11(8):56.
  6. Hu Fa Ming. Journal of Clinical Application in Dermatology. 1985;14(5):277.
  7. Liu Shou Yong. Liaoning Journal of Traditional Chinese Medicine. 1987;11(5):45.
  8. Li Wei. China Journal of Hospital Pharmacy. 1994:14(7):329.
  9. Wang Ren Qun. China Journal of Chinese Medicine. 1994;19(10):631.
  10. Liu Guan Xiang. Shanxi Journal of Traditional Chinese Medicine. 1996;17911):521.
  11. Yan Zhen Hua, et al. Shanxi Journal of Traditional Chinese Medicine. 1996;17(2):83-85.
  12. Zhu Li Hong. China Journal of TCM Information. 1996;3(3):17-20.
  13. Yan Mei Zhen, et al. China Journal of Chinese Medicine. 1998;23(6):375-377.
  14. Hu Cong. Xinjiang Journal of Traditional Chinese Medicine. 1998;16(2):50-53.
  15. Zhang Cun Diao, et al. China Journal of Integrated Splenico-Gastrology. 1997;5(3):168-169.
  16. Li Yan, et al. Journal of Traditional Chinese Medicine Information. 1999;16(4)47.
  17. Zhu Zi Ping, et al. China Journal of Integrated Splenico-Gastrology. 1998;16(1):42-43.
  18. Wu Xin Hua, et al. Xinjiang Journal of Traditional Chinese Medicine. 1998;16(1):42-43.
  19. Xu Ling, et al. Journal of Research in Chinese Medicine. 1997;10(2):31-32.
  20. Hu Shao Ying, et al. Journal of Nanjing University of TCM. 1996;12(5):23-24.
  21. Ni Jia Xiang, et al. China Journal of Anesthesiology. 1995;15(1):21-23.
  22. Wang Yong Jun, et al. China Journal of Integrated Medicine. 1996;16(5):312-314.