Plant Family: 

Licorice belongs to the Fabaceae plant family.  Most of the plants within this family produce fruits (legumes) and are angiosperms. Since this is a family of legumes, the fruits often come from a pod.  Fabaceae is the third largest plant family of angiosperms. This is a very diverse family and most of the plants that fall into the Fabaceae family (to include licorice) are used medicinally.

This is the legume family, above ground parts of licorice look like a type of pea.

 

Habitat & Cultivation: 

Licorice is native to Southern Europe and parts of Asia. Glycyrrhiza lepidota, or American Licorice, is a relative of Glycyrrhiza glabra that can be found throughout the United States and Canada. Licorice can be grown in the US.

 

The use of licorice can be dated all the way back to the “beginning of recorded history”.  In the first century, approximately 40-90 A.D., the plant was listed in Pedanius Dioscordes’ Materia Medica amongst 650 medicinal substances (Fiore, Eisenhut, Ragazzi, Zanchin, & Armanini, 2005).  It was listed as remedy for: asthma, throat issues, ulcers of the mouth and possible use for fertility. It has been noted in ancient: Greek, Italian, Spanish, Iraqi, Iranian, German, Syrian, English and Swedish histories. It was used for non-productive cough, hoarse voice, chest pain, blood stained sputum, burning sensation of the stomach, palpitations, “scabies of the bladder”, kidney pain, kidney stone expulsion, neuralgia, hepatitis, open wounds of the skin, nail granulomas, condyloma, genital ulcers and pterygium.  The most interesting report was that it could increase survival in the desert if it is held in the mouth, along with eating mares milk cheese, could allow the user to go 12 days without water (Fiore, Eisenhut, Ragazzi, Zanchin, & Armanini, 2005).

 

Parts Used/Collection: 

The root is for medicinal preparation in a tincture, infusion or decoction.

 

Herbal Actions: 

  • Demulcent

  • Expectorant

  • Mild laxative

  • Anti-inflammatory

  • Adrenal tonic - very mild adaptogen

  • Antiviral

  • Anti-hepatotoxic

  • Antispasmodic

 

 

Indications: 

  • Fever

  • Prevent adrenal failure

  • Genital–urinary system

    • Bladder and kidney issues (kidney stones

  • Respiratory diseases

    • Mucus congestion

    • Asthma

    • Coughing

    • Lung disease

  • Skin diseases

    • Cold sores, psoriasis

  • Ulcers (including skin ulcers)

    • Granulomas, Wounds

  • Gastrointestinal system

    • Stomach pains, diseases of liver, mouth ulcerations.

  • Cardiovascular: hypotension

  • Stress

(Nazari et al., 2017).

 

Contraindications:  

  • Licorice may interfere with prescription drugs for heart failure. In the resource that I added to your licorice folder on Moodle, the mechanism by which licorice interferes with medications is explained: it prevents an efflux pump in intestinal cells from eliminating medications and herbal constituents.  It increases absorption, which can have harmful effects if the medication is carefully titrated.

  • Hypertension

    • It needs to be used with warning in women with familial history of pre-eclampsia.

      • The use of licorice during pregnancy is accompanied with reduction of gestational age, preterm delivery, and some change in cognitive dysfunction in children.

  • Hypokalemia ( potassium levels are too low) induced by licorice could increase the risk of heart of failure.

Dosage: 

  • Tincture: 1:5 in 40%

    • 1-3 mL, 3x/day

  • Decoction: ½ - 1 teaspoon of root in 1 cup of water

    • Boil, then simmer for 10-15 minutes. Drink 3x/day

  • Licorice is rarely dosed as a single herb, it works it’s magic well in formulations where it is a synergizer plant (potentiating the absorption and efficacy of other plants).  It’s too sweet to take alone.

Plant Constituents: 

Glycyrrhizin is the leading active constituent- A sweet-tasting triterpenoid saponin. It increases blood pressure by inhibiting cortisol metabolism in the kidneys, increasing the sensitivity of mineralocorticoid receptors, and decreasing the levels of minerals like potassium in the blood. Also, glycyrrhizin prevents the breakdown of cortisol into cortisone.

 

Other constituents that help licorice are bitters, volatile oil, and linolenic acid.

This is thought to be due to the triterpenoids saponins in licorice, especially glycyrrhizin.  These help “pull” other constituents into solution. Saponins act sort of like emulsifiers, bonding with constituents and solvents to bring them into solution.   Glycyrrhizin is also helpful for promoting the absorption of other herbs in a formula, one mechanism by which it does this is to inhibit P-glycoprotein in the intestines.  P-glycoprotein is an efflux pump that removes medications and plant compounds from intestinal cells, preventing their absorption (so it may also help increase absorption of medications).  There are other constituents within licorice that are also doing this, such as licochalcone A. 

 

System Affinities: 

 

  • GI (gastritis, gastric ulcers, hepatitis)

  • ENMT (reduces dental plaque and aphthous ulcers, reduces HSV)

  • Respiratory (cough, catarrh, bronchitis)

  • CNS (depression in cases of elevated cortisol)

  • Immune (inhibits growth of virus)

  • Endocrine (adrenal fatigue, PCOS, infertility) 

  • GU (prevents bacterial adherence to bladder wall)

  • MSK (rheumatism) ← an antiquated term that meant pain and inflammation throughout the MSK system

 

Energetics: 

 

Sweet, bitter, cooling. VP-, K+

Safety: 

  • May cause GIT upset, edema, and temporary visual disturbance

  • Long term use may reduce thyroid function and basal metabolic rate 

  • “High doses of long-term use may cause headaches, seizures, arrhythmia, amenorrhea, gynecomastia, and hypermineralcorticoidsism” . High doses are contraindicated.  We use licorice as a low-dose added to formulas! It’s magic is in its ability to synergize with herbs and it only takes a tiny amount to bring about this effect (5-10% of a formula).

  • May antagonize/agonize estrogen receptors, decrease testosterone, and increase PTH 

  • Liver disorder, liver cirrhosis, hypertonia, hypokalemia, severe kidney insufficiency. 

  • Low dose formulating with licorice is not associated with the above risks, but since this is misunderstood we avoid use in these particular situations.

Personal Experience: 

I enjoyed this decoction it worked well to suppress a creeping sore throat that was trying to emerge. 

 

Research:

American Botanical Council. (2000). Lemon balm. Accessed 2 Feb 2018.
 

Hoffmann, D. (2003). Medical Herbalism: The Science and Practice of Herbal Medicine. Rochester, VT: Healing Arts Press. 
 

Mills, S., & Bone, K. (2005). The Essential Guide to Herbal Safety. St. Louis, MO: Elsevier Churchill Livingstone.

 

 

 

Licorice (Glycyrrhiza glabra)

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