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Quest Vitamins LTD,
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Aston Science Park,
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Registered in England No. 2530437

Liquorice (Glycyrrhiza glabra)


Once used to manufacture candy, liquorice has numerous health benefits that have been enjoyed throughout the world. One of the most biologically active herbs known, it affects the immune, circulatory, renal, respiratory and Endocrine Systems. Because liquorice acts as an anti-inflammatory, it can be used to treat the symptoms of many external and internal disorders. Recent research has found a use for the liquorice-component, carbenoxolone Sodium, in modern anti-ulcer drugs. In folklore, liquorice root is often used for its estrogenic properties.


Liquorice has been used since ancient times as a food and a medicine. Chinese herbal formulas nearly all contain liquorice, which functions to harmonise the various herbs in each prescription. Liquorice contains a number of active ingredients. Glycyrrhizin possesses anti-inflammatory, Cough-suppressant, antiviral, estrogen-like, and aldosterone-like activities (1). Aldosterone causes fluid retention, increased blood pressure, and Potassium loss in the body. Deglycyrrhizinated liquorice (DGL), therefore, is a safer product, although it may not retain all the benefits of whole liquorice.


Part of the plant used: ROOT.

For Ulcers, take two to four 380-mg tablets of DGL before meals and at bedtime. Use with conventional therapy.

For mouth sores, suck on two to four 380-mg tablets of DGL before meals and at bedtime.

For respiratory problems, take 1 to 2 g of liquorice root 3 times daily for no more than 1 week.

For Eczema, Psoriasis, or Herpes, apply liquorice cream twice daily to the affected area.

For Chronic Fatigue Syndrome, consult a physician. High dosages of whole liquorice are required. Significant side effects may result.


DGL can be effective treatment for Ulcers(2). Liquorice appears to stimulate repair processes and activate defences against further injury in mucous membranes (3,4). Animal studies indicate that DGL may help prevent aspirin-induced ulcers (5). Several studies suggest that DGL is as effective as Zantac drugs. However, unlike conventional Zantac drugs, which work to eradicate ulcers permanently, DGL must be taken continuously to prevent the recurrence of ulcers.

Mouth sores:
Due to its effect on mucous membranes, DGL can also be used to relieve canker sores and other types of mouth sores.

DGL has been used to treat Heartburn, although the exact benefit and mechanism of treatment is unknown.

Skin disorders:
Creams containing whole liquorice can be used to treat Eczema, Psoriasis, and Herpes.

Respiratory problems:
Whole liquorice can be used as an expectorant to treat respiratory problems, including Asthma and Coughing (9,10).

Chronic Fatigue:
Liquorice has recently been recommended as a treatment for Chronic Fatigue Syndrome due to low levels of adrenal hormones. Glycyrrhizin may help alleviate fatigue by mimicking the effects of the natural hormones. This treatment may be potentially dangerous and should only be attempted under medical supervision.

Liquorice has also been suggested for the following: liver diseases (11,12), menopausal symptoms, cancer prevention, High Cholesterol, and Immune System health (13). However, little evidence of its effectiveness are available.


While thorough studies on safety have not yet been conducted, liquorice appears to be non-toxic. Side effects are rare.

Whole liquorice can cause fluid retention, high blood pressure, and loss of Potassium if more than 3 g per day is taken for more than six weeks. Individuals with high blood pressure, heart disease, diabetes, or kidney disease are advised to avoid liquorice root.

Safety in young children, nursing or pregnant women, and patients with severe liver or kidney disease has not been determined.


Liquorice may interfere with corticosteroid treatment, such as prednisone (14). Long-term use of liquorice may be dangerous if one is on digitalis or cardiac glycosides. If one is on thiazide or loop diuretics, use of liquorice may cause excessive loss of Potassium.

Regular use of DGL with aspirin or other anti-inflammatory drugs may help lower the risk of Ulcers.


1. Newall C, et al. Herbal medicines: A guide for health-care professionals. London: Pharmaceutical Press, 1996: 183-184.
2. Schulz V, et al. Rational phytotherapy. New York: Springer-Verlag, 1998: 185.
3. van Marle J, et al. Deglycyrrhizinised liquorice (DGL) and the renewal of rat stomach epithelium. Eur J Pharmacol 72: 219-25, 1981.
4. Johnson B and McIssac R. Effect of some anti-ulcer agents on mucosal blood flow. Br J Pharmacol 1: 308, 1981.
5. Brinker F. Herb contraindications and drug interactions, 2nd ed. Sandy, Oregon: Eclectic Medical Publications, 1998: 92.
6. Morgan AG, et al. Comparison between cimetidine and Caved-S in the treatment of gastric ulceration and subsequent maintenance therapy. Gut 23: 545-551, 1982.
7. Morgan AG, et al. Maintenance therapy: A two-year comparison between Caved-S and cimetidine treatment in the prevention of symptomatic gastric ulcer. Gut 26: 599-602, 1985.
8. Kassir ZA. Endoscopic controlled trial of four drug regimens in the treatment of chronic duodenal ulceration. Ir Med J 78: 153-156, 1985.
9. Amagaya, S., E. Sugishita, Comparative studies of the stereoisomers of glycyrrhetinic acid on anti-inflammatory activities. Journal Pharm. Dyn., 7, 923-928, 1984.
10. Nasyrov, K.M. & D.N. Lazareva. Study of the anti-inflammatory activity glycyrrhizin acid derivatives. Farmakologiia I Toksikologiia, 43(4), 399-404, 1980.
11. Fujisawam, Watanabe, & Kimura. Therapeutic approach to chronic active hepatitis with glycyrrhizin. Asian Medical Journal, 23, 745-756, 1980.
12.Greenberg, H.B., R.B. Polland, et. al. Effect of human leukocyte interferon on hepatitis B virus infectioin in patients with chronic active hepatitis. New England J Of Medicine, 295, 517-522, 1976.
13. Abe, N., E. Takusaburo & N. Ishida. 1982. Interferon induction by glycyrrhizin and glycyrrhetinic acid in mice. Micro and Imm, 26(6).
14. Brinker F. Herb contraindications and drug interactions, 2nd ed. Sandy, Oregon: Eclectic Medical Publications, 1998: 92.

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