1. Abstract
Licorice derived from the root of Glycyrrhiza glabra, is a time-honored botanical used extensively in traditional systems of medicine across Asia and Europe. Rich in glycyrrhizin and flavonoids, it exerts diverse pharmacological actions including anti-inflammatory, mucoprotective, antiviral, and adaptogenic effects. This review outlines its phytochemical composition, mechanisms of action, clinical relevance across gastrointestinal, respiratory, and endocrine systems, along with safety considerations and recommended usage.
2. Introduction
Licorice root has been valued for centuries in Ayurveda, Traditional Chinese Medicine, and Unani medicine for its soothing, anti-inflammatory, and harmonizing properties. It is often used as a base or adjunct in multi-herbal formulations due to its synergistic effects. Modern research supports its benefits in gastric ulcers, adrenal support, respiratory infections, and skin conditions, especially when standardized for glycyrrhizin or deglycyrrhizinated forms.
3. Composition and Mechanism of Action
Composition:
- Glycyrrhizin (triterpenoid saponin) – Main active compound [1]
- Liquiritigenin, glabridin (flavonoids) – Antioxidant and estrogenic activities [2]
- Isoflavones, coumarins, and polysaccharides [3]
Mechanism of Action:
- Anti-inflammatory: Inhibits 11β-hydroxysteroid dehydrogenase, enhancing cortisol action locally [4]
- Mucoprotective: Stimulates mucus secretion and cell regeneration in the gastric lining [5]
- Antiviral Activity: Inhibits viral replication in hepatitis and respiratory viruses [6]
- Adaptogenic & Endocrine Modulation: Supports adrenal function, especially in chronic stress [7]
4. Clinical Benefits
Gastrointestinal Support
- DGL (Deglycyrrhizinated Licorice) helps heal gastric and duodenal ulcers [5]
- Reduces symptoms of GERD and gastritis
Respiratory Health
- Expectorant and anti-inflammatory in bronchitis, cough, and sore throat [6]
Adrenal & Hormonal Balance
- May support cortisol regulation and reduce fatigue during chronic stress [7]
- Mild estrogenic activity is beneficial in menopausal symptoms [8]
Skin Health
- Useful in hyperpigmentation and eczema due to glabridin and flavonoids [9]
5. Dosage & Administration
Oral Use:
- Standard Extract (Glycyrrhizin 10–20%): 150–300 mg/day
- DGL (Deglycyrrhizinated Licorice): 380–760 mg 20 minutes before meals for gastric issues
- Tea or powder: 1–3 g/day
Topical Use:
- Used in creams and gels for skin brightening and inflammation
Note: Long-term or high-dose glycyrrhizin use can lead to mineralocorticoid effects; prefer DGL in chronic administration.
6. Safety & Considerations
- Potential for Hypertension and Edema: Due to pseudoaldosteronism with high-dose glycyrrhizin [10]
- Electrolyte Imbalance: May lower potassium levels with prolonged use
- Pregnancy: Use only under supervision; avoid in high doses
- Drug Interactions: May interfere with diuretics, corticosteroids, and antihypertensives
7. Discussion
Licorice is a versatile adaptogen and mucoprotective herb with substantial clinical relevance, especially in gastrointestinal and respiratory care. The form of extract-glycyrrhizin-containing vs. DGL should be selected based on the indication and duration. Its benefits in adrenal fatigue and mucosal healing make it a cornerstone botanical, although care must be taken to prevent glycyrrhizin-related side effects.
8. Conclusion
Licorice (Glycyrrhiza glabra) stands as a powerful herbal agent with documented benefits in digestive health, respiratory infections, stress resilience, and skin care. When used in the appropriate form and dose, it offers a high therapeutic value. Standardization and clinical vigilance ensure it remains both effective and safe in modern herbal practice.
References
- Fiore C, et al. “Glycyrrhiza glabra and glycyrrhizin: A review.” Phytother Res, 2005.
- Armanini D, et al. “Liquiritigenin and glabridin in estrogenic balance.” Steroids, 2002.
- Wang ZY, Nixon DW. “Licorice in cancer prevention and therapy.” Nutr Cancer, 2001.
- Stewart PM, et al. “Licorice and 11β-HSD inhibition.” Lancet, 1987.
- Rees WD, et al. “Protective effects of DGL in ulcer therapy.” Gut, 1979.
- Pompei R, et al. “Antiviral activity of glycyrrhizin.” Antiviral Res, 1983.
- Biondi DM, et al. “Adaptogenic effects of licorice root.” Fitoterapia, 2001.
- Somjen D, et al. “Estrogen-like activity of glabridin.” J Steroid Biochem Mol Biol, 2004.
- Fu B, et al. “Topical licorice for hyperpigmentation.” Int J Dermatol, 2005.
- Stormer FC, et al. “Licorice-induced hypertension and pseudoaldosteronism.” J Hum Hypertens, 1993.
FDA Disclaimer
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.