Gan Cao – Licorice root – “Sweet Herb”

Nature: sweet, neutral

Enters: ALL – especially Heart, Lung, Stomach, Spleen

Actions: Tonifies spleen Qi; moistens the Lungs to stop coughing, eases difficult breathing; relaxes the muscles, eases spasms to relieve pain; clears heat; eliminates toxicity; conducts herbs into the twelve channels; coordinates herbs: reduces side effects of some herbs, antidotes some poisons, harmonizes cold and warm herbs, protects the spleen from cold herbs, mitigates the purging function of purgatives and lightens other violent qualities of herbs.

Indications:
• Spleen Qi deficiency: poor appetite, loose stool, fatigue, shortness of breath.
• Spasm and pain in the epigastrium, abdomen, limbs (including when due to malnutrition or cold).
• Fire-toxicity: carbuncles, poisoning from food or herbs, sores, sore throat.
• Used internally and externally to antidote poisons.
• Heat or cold in the Lungs: coughing and wheezing.
• Increases duration and strength of effects of cortisol: useful for low adrenal function.
• Anti-inflammatory effects (glycyrrhetinic acid [weaker than cortisol]).
• Useful for chronic asthma. Used with Ku shen and Ling zhi in the simplified ASHMI formula for asthma.
• Relieves and prevents ulcers (DGL can be used if there is concern of sodium retention and the resulting hypertensive effect).
• May possess anti-neoplastic effects.
• Can cause water retention: aldosterone-like effects, decreased urination, decreased sodium excretion – long-term use may cause hypertension and/or edema.
Zhi gan cao: honey fried – more tonic, better than the raw herb for moderating spasms. This form is used in most cases, except when clearing heat and toxicity (for which the raw herb is preferred).
• Raw Gan cao is more detoxifying and heat clearing than the prepared form.
Gan cao shao: tips of the root – can disinhibit urination and free strangury.
HF: A supplement with an anti-Gu nature, possessing acrid, toxin-resolving qualities, useful in Gu Zheng (Gu parasites) formulas.
SD: May help antidote lead poisoning.
DY: With Bai shao to engender Yin (sour + sweet), calm the liver, fortify the spleen, supplement Qi and blood, harmonize the liver and spleen, soothe the sinews, and stop pain. For indications such as:
– 1. Weakness in the lower limbs and spasms and pain in the limbs due to disharmony between the Qi and the blood which causes inadequate nourishment of the sinews and vessels.
– 2. Abdominal pain due to liver-spleen disharmony. If either disorder is accompanied by cold signs, use wine mix-fried Bai shao and mix-fried Gan cao. If the disorder is accompanied by heat signs, use raw Bai shao (or Chi shao) and raw Gan cao.
– 3. Headaches due to blood deficiency. (Add He shou wu, Bai ji li, and Jiang can.)
• The combination of Bai shao and Gan cao is very effective for numerous problems accompanied by spasms and pain, such as gastritis or colitis, spasm of the gastrocnemius muscle in the leg, contraction of the limbs, tendinitis, lateral costal pain, and hiccups or stubborn vomiting caused by spasm of the diaphragm.
Gan cao can moderate the cold nature of Hua shi and protect the middle jiao, while Hua shi can prevent stasis due to the sweet flavor of Gan cao. As a pair, they clear heat, eliminate summer-heat, disinhibit urination without damaging the middle burner, and free strangury. For such indications as:
– 1. Fever, vexation, agitation, thirst, vomiting, diarrhea, and dysuria due to attack of summer-heat with internal and external heat. (Liu Yi San)
– 2. Turbid strangury.
– 3. Stone and/or sand strangury.
– For these indications, Gan cao shao is superior to regular Gan cao.
• With Jie geng to clear heat, transform phlegm, disinhibit the throat and stop pain, evacuate pus, and resolve toxins.
– 1. Pulmonary abscess with cough, expectoration of profuse, purulent phlegm, and chest oppression and pain due to heat stasis in the chest. (Jie Geng Tang)
– 2. Pain, redness, and swelling of the throat due to heat (deficient or excess, external or internal).
– 3. Loss of voice and/or hoarse or husky voice.
– For indications 2 and 3, the combination can be reinforced by adding He zi, as in He Zi Tang. For these indications, in cases of Lung dryness, honey mix-fried Jie geng should be used.
Gan cao is incompatible with pork, seaweed (particularly Hai zao), and Chinese cabbage.
• In cases of edema, oliguria, anuria, or hypertension, the dosage of Gan cao must be moderate (3-6g) and its administration should be of short duration. In other cases, for prolonged administration, a dosage of 10g per day should not be exceeded.
• Note: Sionneau lists the usual dosage of Gan cao at 6-10g.
K&R: Anti-inflammatory, anti-allergic, immune strengthener, estrogenic, luteotropic, antispasmodic, antiulcerative, vagolytic, febrifuge, antitussive, aldosterone stimulant, MAOI, stimulates the adrenal cortex.
• Improves fat digestion, reverses degeneration of liver cells by improving detoxification – for fatty liver, chronic hepatitis, to lower cholesterol.
• Increases interferon production.
• Eye drops: for conjunctivitis, blepharitis.
• Chronic gum infections.
• Prolonged use is suitable only for the water yin type (since it can lead to K+ loss and edema).
• Earth, water, and metal yin.
Earth: GI ulcer and spasm, glossitis, stomatitis, herpes simplex infection, tooth plaque.
Water: low immune function, depression, chronic infection, gonadal insufficiency, trichomonas infection.
Metal: recurring, chronic respiratory tract infection, cough.
BII: Heals peptic ulcers (DGL preferred), estrogenic activity, aldosterone-like action (can cause sodium retention and hypertension – a high potassium, low sodium diet may prevent this), anti-inflammatory (cortisol-like action), anti-allergic, antihepatotoxic, antineoplastic, expectorant, antitussive, antiviral.
• Possible use in: HIV (seems to halt progress of the disease, may prevent decline of CD4s and CD8s), aphthous stomatitis (mouthwash), eczema, heartburn, hepatitis, inflammation, menopausal symptoms, periodontal disease.
JC: Aperient, demulcent, emollient, pectoral, slight stimulant, sialogogue, expectorant.
• Laxative or mildly purgative (by dose) to the entire intestinal tract: a moderate dose makes liquid stools within 3-12 hours (3-6 on an empty stomach).
• Useful for hemorrhoids.
• Healing to the glandular system.
• Heals mucous membranes.
Yoga: Yashti Madhu (honey stick): V, P-; K+(if used long term)
• Demulcent, expectorant, tonic, rejuvenative, laxative, sedative, nourishes the brain, increases cerebrospinal fluid.
Sattvic – calms the mind, nurtures the spirit.
• A large dose is a good emetic for cleansing the Lungs and stomach of Kapha.
Hsu: Detoxifies bacterial toxins, poisonous foods and drugs, toxins of metabolic products.
• Antispasmodic, inhibits gastric secretions caused by histamine, anti-inflammatory, antitussive, antiallergic, antiulcerative, expectorant, adrenocortical hormone-like effects.
HF: (The words of Zhang Xichun:) If processed, the tonic properties of licorice become enhanced, while if left unprocessed, it not only tonifies the center, but also disinhibits. It is therefore appropriate for the treatment of cholera. The theory that raw licorice has a disinhibiting effect can easily be proven in clinical practice. I once treated the child of a Mr. Wang from Kaiyuan. Endowed with a weak spleen and stomach, the boy suffered from serious indigestion and kept throwing up his food. Also, his urination was inhibited, producing edema in virtually every part of his body, as well as a large and distended belly. I prescribed fine licorice powder, to be mixed with an equal amount of the Western drug Pepsinum. I had him take one qian (3g) of this mixture three times per day. After several days, the vomiting stopped, the urination returned to normal, and the swelling and distention disappeared.
My friend Wei Ziba made it a habit to put some licorice in his teapot every day, pour hot water over it, and drink it like a tea. After about ten days, he noticed that both his stool and his urination started to get quite busy, and he stopped drinking the licorice water. When he saw me later, he related this to me and asked why an herb that is usually thought of as a tonic can disinhibit urination and bowel movements. I answered: “When cooked or processed, licorice tonifies; when used unprocessed, it disinhibits. Even though you put the herb into a teapot with hot water, it never got cooked. Therefore, its effect was still close to the raw herb, and therefore could disinhibit.”
Li Zibo told the story of a child suffering from abdominal pain. The doctor said that frequent consumption of licorice decoction could cure the problem. Because the patient drank too much of the licorice decoction, urination became inhibited and symptoms of edema and abdominal distention emerged. The boy lived close to the train station, where there were always wagons loaded with licorice. His sister often brought some of it home so they could chew on it, and as this became a daily habit, his edema and distention gradually disappeared.
These examples demonstrate that the functions of unprocessed licorice and processed or cooked licorice are fundamentally different. When working with licorice, therefore, shouldn’t we always consider the raw or processed/cooked state of the herb as an integral part of the prescription?
CHA: (Karen S Vaughan, 11-17-2000):
As far as I can determine blood pressure has never been known to be raised from properly prescribed herbal preparations containing licorice root, of either the European or Chinese varieties. It has however been found to be raised in persons consuming large quantities of (real) licorice candy such as Panda licorice, at doses as low as 1 ounce candy daily and can also be attributable to (real) licorice flavored alcoholic drinks. Candy consumption and extrapolation from constituent data are the root of warnings about licorice and blood pressure. Quantity and refinement issues are both factors with licorice candy. There is a significant difference in aqueous extractions and alcohol extractions in licorice. My information is that one would need 10-45 grams per day [to raise blood pressure], which is a lot of licorice. There are cases of persons who have unusual sensitivity (almost allergy) to licorice, plain or DGL which may manifest with high blood pressure. I find oedemic, not diuretic indications for licorice in my western sources. Reduced excretion of potassium (and its replacement) can be achieved with the addition of dandelion to formulas. Some constituent information which may or may not be relevant to aqueous extractions of Gan cao: One active ingredient in licorice, glycyrrhizin, and it main gut metabolite in humans, glycyrrhetic acid, both prolong the effects of cortisol, by creating an aldosterone-like agonist effect, thereby causing sodium retention and potassium depletion at the distal tubule in the nephron. Those on blood pressure medicines such as Lasix (furosemide) or hydrochlorothiazide, heart medicines such as Lanoxin (digoxin), or cortisone-type drugs, including prednisone may be susceptible to cross-reactions from constituents in licorice, especially in concentrated extracts, candy or licorice liqueurs. For over forty years, glycyrrhizin has been a prescription drug in Japan to treat inflammatory illnesses such as ulcers and chronic liver disease. It is also used to decrease allergic reactions to other drugs. Glabridin, which is not water extracted, but may be present in other preparations, has strong antioxidant properties. Researchers using a highly refined licorice extract suggest that chemicals in glycyrrhizin called triterpenoids may be effective against cancer. They may block the production of a prostaglandin that may be responsible for stimulating the growth of cancer cells – and help get rid of cancer-causing invaders. Triterpenoids have been shown in test tubes to stunt the growth of rapidly multiplying cells, like cancer cells, and they may even help precancerous cells return to normal. Glycyrrhetic acid is also antitumoral in low doses in estrogen sensitive cancers, operating by tying up estrogen receptors. Large doses(> 300mg extract, >2 gm powder, or >4 ml fluid extract) of licorice may, however, show more of the estrogenic effects due to the higher availability of the isoflavones. The antagonistic effects occur by competing for receptor sites, but once all empty sites are filled, there is no greater antagonistic effect. There is some early indication for use in AIDS treatment but the research is difficult to interpret accurately. The American species (Glycyrrhiza lepidota) does not share the potential for blood pressure elevation in concentrated doses that European and Asian species have.

Dose: 2-12g

3 comments on “Gan Cao – Licorice root – “Sweet Herb”

  1. Anonymous says:

    Does DGL have the same properties as plain licorice for removing toxins, moderating and guiding the herbs to all the meridians or is plain licorice more suitable?

  2. Dee says:

    Yes that is my question as well. Also do you know if DGL protect the stomach when one must use blood moving herbs.

    • Peter Borten says:

      No, I don’t think DGL has the same medicinal value that whole licorice root does. Glycyrrhizin appears to be responsible for much of licorice’s therapeutic value. Without it, DGL is a soothing emollient, but probably not much else.

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