Latin Names- Glycyrrhiza glabra, Glycyrrhiza uralensis (Chinese licorice)
As an herbal remedy licorice root has a long history in both Eastern and Western traditions. Most licorice is grown in Greece, Turkey, and Asia. Peeled licorice root is available in dried and powdered forms.
Licorice root is also made into capsules, tablets, and liquid extracts. Licorice contains a compound called glycyrrhizin (or glycyrrhizic acid). Licorice can be found with glycyrrhizin removed; the product is called DGL (for "deglycyrrhizinated licorice").
Licorice root has been used as dietary supplement in the hope of improving problems such as stomach ulcers, bronchitis, and sore throat, as well as infections caused by viruses, such as hepatitis.
In terms of research, a review of several clinical trials found that glycyrrhizin might reduce complications from hepatitis C in some patients. However, there is not enough evidence to confirm that glycyrrhizin has this effect.
There are not enough reliable data to determine whether licorice is effective for stomach ulcers.
Side Effects and Cautions Summary
- In large amounts, licorice containing glycyrrhizin can cause high blood pressure, salt and water retention, and low potassium levels, which could lead to heart problems. DGL products are thought to cause fewer side effects.
- The safety of using licorice as a supplement for more than 4 to 6 weeks has not been thoroughly studied.
- Taking licorice together with diuretics (water pills) or other medicines that reduce the body’s potassium levels could cause dangerously low potassium levels.
- People with heart disease or high blood pressure should be cautious about using licorice.
- When taken in large amounts, licorice can affect the body’s levels of a hormone called cortisol and related steroid drugs, such as prednisone.
- Pregnant women should avoid using licorice as a supplement or consuming large amounts of licorice as food, as research suggests it could increase the risk of preterm labor.
- Tell your health care providers about any complementary and alternative practices you use. Give them a full picture of what you do to manage your health to help ensure coordinated and safe care. Complementary or alternative therapy should not be used in place of conventional medical care or to delay seeking that care.
- National Center for Complementary and Alternative Medicine. Hepatitis C and Complementary and Alternative Medicine: 2003 Update. National Center for Complementary and Alternative Medicine Web site. Accessed on July 12, 2007.
- Licorice (Glycyrrhiza glabra). In: Coates P, Blackman M, Cragg G, et al., eds. Encyclopedia of Dietary Supplements. New York, NY: Marcel Dekker; 2005:391–399.
- Licorice. Natural Medicines Comprehensive Database Web site. Accessed on July 12, 2007.
- Licorice (Glycyrrhiza glabra L.) and DGL (deglycyrrhizinated licorice). Natural Standard Database Web site. Accessed on July 12, 2007.
- Licorice root. In: Blumenthal M, Goldberg A, Brinckman J, eds. Herbal Medicine: Expanded Commission E Monographs. Newton, MA: Lippincott Williams & Wilkins; 2000:233–239.
For More Information
The National Center for Complementary and Alternative Medicine (NCCAM) Clearinghouse
The NCCAM Clearinghouse provides information on CAM and NCCAM, including publications and searches of Federal databases of scientific and medical literature. The Clearinghouse does not provide medical advice, treatment recommendations, or referrals to practitioners.
NIH Office of Dietary Supplements
Web site: ods.od.nih.gov
NIH National Library of Medicine’s MedlinePlus
Licorice Root Listing: www.nlm.nih.gov/medlineplus/druginfo/natural/patient-licorice.html
Source: National Center for Complementary and Alternative Medicine, Licorice Root fact sheet, Created June 2006, Updated June 2008