Licorice Root

Effects and Benefits

Core Identification

Common Names:
- Licorice Root
- Liquorice
- Sweet Root
- Gan Cao (Chinese)
- Sweetwood
- Mulethi (Ayurvedic)

Latin Name: Glycyrrhiza glabra

Category: Herb

Uses

Traditional Uses

• Digestive tonic and stomach ulcer remedy - Ancient Egypt, Greece, and China dating back 4,000+ years
• Respiratory expectorant for coughs, bronchitis, and lung conditions - European and Chinese traditional medicine
• Adrenal support and energy tonic - Traditional Chinese Medicine (one of the most important herbs, entering all twelve meridians)
• "Harmonizer" herb added to formulas to moderate harsh effects of other herbs - Chinese herbal tradition

Modern Uses

• Peptic and Duodenal Ulcers - Mucoprotective, increases gastric mucus production, inhibits H. pylori | Research quality: Strong
• Key findings: DGL (2.3-3.8 g/day for 12-16 weeks) combined with antacids shown as effective as cimetidine and ranitidine in healing gastric and duodenal ulcers in controlled clinical trials

• Source citations: Bone, Kerry - A Clinical Guide to Blending Liquid Herbs; Bartram's Encyclopedia

• Adrenal Insufficiency/Fatigue - Inhibits enzyme that breaks down cortisol, extending its action; ACTH-like activity on adrenal cortex | Research quality: Strong

• Key findings: Contains glycosides remarkably similar to body steroids; effective in maintaining electrolyte equilibrium in Addison's disease patients

• Source citations: Bone, Kerry - A Clinical Guide to Blending Liquid Herbs; Bartram's Encyclopedia

• Respiratory Conditions - Antitussive, expectorant for dry cough, bronchitis, upper respiratory catarrh | Research quality: Moderate

• Key findings: Oral glycyrrhetinic acid demonstrated antitussive effect similar to codeine in animal studies

• Source citations: Bone, Kerry - A Clinical Guide to Blending Liquid Herbs

• Polycystic Ovary Syndrome (PCOS) - Combined with white peony (Paeonia lactiflora) to lower LH/FSH ratio and reduce ovarian testosterone | Research quality: Moderate

• Key findings: Combination (6g/day each herb for 24 weeks) induced regular ovulation and resulted in pregnancies in clinical studies

• Source citations: Bone, Kerry - A Clinical Guide to Blending Liquid Herbs

• Inflammatory Conditions - Anti-inflammatory effects comparable to prednisolone and dexamethasone in topical applications | Research quality: Moderate

• Key findings: Glycyrrhetinic acid and glycyrrhizin demonstrated significant anti-inflammatory effects in arthritis models

• Source citations: Bone, Kerry - A Clinical Guide to Blending Liquid Herbs

• Antiviral Support - Topical application for herpes simplex, cold sores | Research quality: Moderate

• Key findings: Glycyrrhizin active against HSV, varicella-zoster virus in vitro; topical use indicated as systemic antiviral effects may be limited after oral ingestion
• Source citations: Buhner - Herbal Antivirals; Bone, Kerry - A Clinical Guide to Blending Liquid Herbs

Active Compounds

Primary Active Ingredients:
- Glycyrrhizin (glycyrrhizic acid) - Triterpenoid saponin responsible for sweetness and most therapeutic/adverse effects; inhibits cortisol metabolism, provides anti-inflammatory and antiviral activity
- Glycyrrhetinic acid (GA) - Metabolite of glycyrrhizin formed after oral ingestion; responsible for aldosterone-like effects
- Glabridin - Isoflavonoid with antioxidant, estrogenic, and anti-inflammatory properties; protects LDL from oxidation
- Flavonoids (liquiritigenin, isoliquiritigenin) - Contribute to antispasmodic, antimicrobial, and gastroprotective effects
- Isoflavones - Provide mild phytoestrogenic activity

Dosage Information

Standard Dosage:
- Form: Dried root (tea/decoction)
- Amount: 1-5 grams per day
- Frequency: Three times daily before meals

Therapeutic Dosage:
- Form: Liquid extract (1:1)
- Amount: 2-5 ml per day
- Purpose: Digestive, respiratory, or adrenal support
- Duration: 4-6 weeks maximum without supervision

DGL (Deglycyrrhizinated Licorice) Dosage:
- Form: Chewable tablets
- Amount: 760-1520 mg three times daily
- Purpose: Ulcer healing, digestive support without cardiovascular side effects
- Duration: Can be used longer term than whole licorice

Maximum Safe Dosage:
- Daily maximum: Generally 5-15 g dried root; extracts standardized to 200-600 mg glycyrrhizin daily
- Warning threshold: Do not exceed 4-6 weeks of continuous use at therapeutic doses; monitor for edema, blood pressure changes

Bioavailability Notes:
- Glycyrrhizin is converted to glycyrrhetinic acid by intestinal bacteria after oral ingestion
- Peak plasma levels occur 10-24 hours after ingestion due to enterohepatic circulation
- Higher grades of licorice extracts contain higher glycyrrhizin concentrations

How to Take It

Timing:
- Take before meals for digestive support
- DGL should be chewed 20 minutes before meals or between meals for ulcer healing
- For respiratory conditions, take as needed throughout the day

Synergies - What It Works Well With

Complementary Supplements:
1. White Peony (Paeonia lactiflora) - Traditional combination for PCOS, muscle cramps, dysmenorrhea; equal parts of each herb | Approved combination in Japan for clinical use
2. Marshmallow Root - Combined demulcent action for digestive and respiratory soothing | Enhanced mucosal protection
3. Ginger - Traditional pairing for colds, flu, respiratory congestion | Synergistic warming and expectorant effects
4. Glycine and L-Cysteine - Can reduce risk of pseudoaldosteronism when using high-dose licorice long-term | Protective effect documented with IV formulations in China
5. Iceland Moss - Traditional combination for wasting and cachexia | Nutritive and restorative

Avoidance - What NOT to Combine With

Supplement Interactions:
1. Stimulant Laxatives (Senna, Cascara) - Compounded potassium depletion | Risk of severe hypokalemia

Drug Interactions:
1. Corticosteroids (Prednisone, Hydrocortisone) - Licorice inhibits cortisol breakdown, potentially increasing steroid effects | May require dose adjustment | Severity: Moderate
2. Thiazide and Loop Diuretics - Combined potassium-depleting effects | Risk of severe hypokalemia | Severity: Severe
3. Digoxin/Cardiac Glycosides - Hypokalemia from licorice increases sensitivity and toxicity risk | Severity: Severe
4. Antihypertensive Medications - Licorice raises blood pressure, potentially counteracting treatment | Severity: Moderate
5. Warfarin and Anticoagulants - Potential interaction affecting drug metabolism | Severity: Moderate
6. Oral Contraceptives - Slight possibility glycyrrhizin/glycyrrhetinic acid may counteract efficacy | Severity: Mild
7. MAO Inhibitors - One variety (G. uralensis) has MAO-inhibiting properties | Severity: Moderate

Food Interactions:
- High-sodium diet: Exaggerates sodium-retaining and blood pressure effects of licorice
- Maintain adequate potassium intake when using whole licorice preparations

Safety Information

Contraindications:
- Hypertension (high blood pressure)
- Cardiovascular disease, congestive heart failure
- Kidney disease or insufficiency
- Liver cirrhosis or cholestatic liver disorders
- Hypokalemia (low potassium)
- Pregnancy (may affect hormone levels; some associations with preterm birth)
- Edema or fluid retention conditions

Side Effects:
- Common (with prolonged use/high doses): Sodium and water retention, edema (face and ankles), elevated blood pressure
- Serious: Pseudoaldosteronism (hypertension, hypokalemia, weak limbs, headache, dizziness)
- Rare: Muscle weakness or paralysis, cardiac arrhythmias (from severe hypokalemia)

Long-Term Use:
- Whole licorice preparations should not be used continuously for more than 4-6 weeks without professional supervision
- DGL can be used longer term as glycyrrhizin has been removed
- If using long-term, follow a high-potassium, low-sodium diet
- Monitor blood pressure regularly
- Consider adding potassium supplementation (up to 5,000 mg daily) and glycine (2,000 mg daily) to reduce risk of pseudoaldosteronism
- Elderly patients and those with cardiac, renal, or hepatic conditions should avoid prolonged use of glycyrrhizin-containing preparations

Special Precautions:
- Discontinue 2 weeks before surgery due to potential effects on blood pressure and electrolytes
- Nursing mothers should use cautiously
- Use DGL form for digestive support to avoid systemic effects

Primary Uses At-a-Glance

Primary: Digestive support (ulcers, gastritis, GERD), Respiratory conditions (cough, bronchitis), Adrenal support/fatigue, Harmonizing agent in herbal formulas

Secondary: PCOS (with white peony), Inflammatory conditions, Topical antiviral (herpes), Menopausal support, Throat soothing

Sources

Local Library:
- Bone, Kerry - A Clinical Guide to Blending Liquid Herbs
- Bartram, Thomas - Bartram's Encyclopedia of Herbal Medicine
- Buhner, Stephen Harrod - Herbal Antivirals
- Buhner, Stephen Harrod - Herbal Antibiotics
- Brewer, Sarah - TDT Encyclopedia of Vitamins
- Tierra, Michael - The Way of Herbs
- Stein, Diane - Healing Herbs A to Z
- DeBaggio, Thomas - The Encyclopedia of Herbs
- Simon, David - The Chopra Center Herbal Handbook
- Blankespoor, Juliet - The Healing Garden
- Grogan, Barbara Brownell - Healing Herbs Handbook
- Mars, Brigitte - The Home Reference to Holistic Health and Healing
- Pursell, J.J. - The Woman's Herbal Apothecary
- Todd, Jude - Jude's Herbal Home Remedies
- Lust, John - The Natural Remedy Bible
- Shea, Bridgette - Handbook of Chinese Medicine and Ayurveda

General Knowledge:
- German Commission E Monographs
- ESCOP Monographs