Individual Herbs Notebook

甘草 Gan Cao

Translation: Sweet Grass

Pharmaceutical: Radix Glycyrrhizae
Taxonomy: Glycyrrhiza uralensis seu glabra seu inflata

Other names: Liquorice Root / Yashtimadhu यष्टिमधु / Asl-us-soos السوس

Category: Herbs that Tonify Qi


Properties: Sweet, slightly cold

Meridans Entered:
Primary: Heart, Lung and Spleen (and all 12 meridians)
Extraordinary Vessels: Yin Qiao

Traditional Actions/Indications:
  1. Tonifies the Spleen and augments Qi
    Spleen Qi Deficiency with shortness of breath, lassitude and loose stools
    Qi and Blood Deficiency with an irregular pulse and/or palpitations
    Heart Qi Deficiency or Heart Yang Deficiency
  2. Moistens the Lungs, resolves Phlegm and stops coughing
    Lung Heat or Cold
    Productive or non-productive coughing
  3. Moderates spasms and alleviates pain
    Painful muscle spasms of the abdomen and legs
  4. Clears Heat and relieves Fire Toxicity
    Raw for Toxic Heat with sore throat or carbuncles and sores (Chuang Yung)
  5. Antidote for many toxic substances (internal and topical)
    Poisoning
    Bites (after washing the wound, chew Gan Cao and apply a thick layer on the bite wound, changing whenever it dries out; Bao Xiang-Ao, 1846, New Compilation of Proven Formulas)
  6. Moderates and harmonizes the harsh properties of other herbs and guides the herbs to all twelve channels
    Often added in small doses to harmonise formulas
  7. Tonifies the Qi while suppressing Parasites
    Gu Sydnrome (Fruehauf, 1998)
    Chronic inflammatory disease (Fruehauf, 2015)
  8. Aids fasting
    Mentioned in the Shen Nong Ben Cao Jing as part of the superior class of herbs which can, with protracted taking, make the body light and prolong life. This may suggest it was part of supplementing the diet when engaging in an "avoiding grain" (Bigu 辟穀) fasting regime to cultivate life (Yangsheng 養生).

Suggested Daily Dosage: Typically 1.5-9g in decoction. Large doses can be up 30g.

Cautions: It is contraindicated for combining with Hai Zao, Da Ji, Gan Sui and Yuan Hua because of "eighteen antagonisms". It is also contraindicated in cases of dampness obstruction in middle energizer and edema because it can help dampness obstruct qi, and it is prohibited from long-term usage in large dosage (more than 20g/day) and should be avoided or used with extreme caution in patients with high blood pressure because it may raise aldosterone levels in the blood causing retention of sodium.

The NHS recommends avoiding during pregnancy.

Interactions:

Notable Constituents: For a comparison, see Zhang et al (2018). A Systematic Review of the Comparison of Three Medicinal Licorices, Based on Differences of the Types and Contents about Their Bioactive Components. . J Chem Biol Pharm Chem, Vol.1 No.1: 03.

Notes:

Liu Lihong (2019) reflects on the centrality of this herb in the Shang Han Lun, surmising that it is because it's sweet taste, neutral temperature and yellow colour make it the chief of herbs for the Earth element.

Li Shizhen's Ben Cao Gang Mu describes liquorice as "Guo lao 國老, 'nation’s elder,' a designation for the Emperor's teacher, who even the emperor answers to. He says it treats:

"Cold and hot evil qi affecting the five long-term depots and six short-term repositories. It hardens sinews and bones. It stimulates the growth of muscles and flesh. It doubles the strength of Qi. [It dissolves] swelling associated with wounds
caused by metal objects/weapons. It resolves poison. Ingested over a long time it extends the years... It warms the center and causes the discharge of Qi. [It controls] vexation, a sensation of fullness and shortness of [breath] qi. It is the essence of the nine continents, it pacifies and harmonizes the 72 stones/minerals and the 1200 kinds of herbs.

It controls painful cold in the abdomen. It serves to cure fright epilepsy. It eliminates abdominal bloating and fullness. It supplements and boosts the five long-term depots. [It controls] internal harm caused by kidney qi. It prevents one’s yin [(i. e., genital) organs] from dysfunction. It controls urinary dripping with blood of women and lower back pain. It is used as an additive to all [medication aimed at] depletion and much heat. Zhen Quan. It pacifies the Hun-soul and stabilizes the Po-soul. It supplements in the case of the five kinds of exhaustion and seven kinds
of harm, and all kinds of depletion injury. [It controls] fright palpitation, vexation with heart-pressure and forgetfulness. It frees the passage through the nine orifices.
It opens the passage through the hundreds of vessels. It boosts the essence/sperm and nourishes the qi. It strengthens sinews and bones.

Used raw it drains fire heat. Used processed it disperses cold from the body’s exterior, removes throat
pain, eliminates evil heat, and slows down the proper qi. It nourishes the yin blood, supplements spleen and stomach and supplies the lung with moisture.

It lets one vomit pus and blood from a dysfunctional lung, and dissolves the sores and impediment-illnesses of five possible effusions. [Wang] Haogu. It resolves fetal poison and fright epilepsy of children. It makes fire descend and ends pain." (trans. Unsculd, 2022).

Appears in 459 formulae listed on this site: (click to display)
Research Links & References: (click to display)
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