Licorice is an herb that lends flavor to many foods and beverages. The plant's roots are used in traditional medicine to treat a wide variety of disorders, including gastrointestinal complaints, bronchitis, tuberculosis, malaria, osteoarthritis, liver disease, systemic lupus erythematosus and chronic fatigue syndrome. However, while licorice contains beneficial phytochemicals, it also contains glycyrrhizic acid, which is associated with side effects. To counter this, a modified form of the botanical medicine, known as deglycyrrhizinated licorice, or DGL licorice, is available. Although considered safer, DGL licorice may still pose certain health risks.
According to InteliHealth.com, you should not use licorice or DGL licorice if you have a known allergy to other plants in the Fabaceae family, also known as the pea or legume family. Common symptoms of an allergic reaction include hives or rash, swelling of the extremities or tongue and difficulty breathing.
The University of Maryland Medical Center says that even though most side effects are attributed to high doses of licorice or preparations in which the glycyrrhizic acid content has not been removed, you should also avoid DGL licorice if you have a history of diabetes, edema, high blood pressure, or heart, kidney or liver disease.
Licorice compounds may behave like adrenal hormones in the body, such as estrogen and testosterone. This means that all licorice preparations should be avoided by women with a hormone-driven condition, such as breast, uterine or ovarian cancer or endometriosis or uterine fibroids, and by men who have low testosterone levels. This also means that licorice, including DGL licorice, may reduce the effectiveness of hormone replacement therapy and birth control pills.
Both whole licorice and deglycyrrhizinated licorice interfere with many other medications, including diuretics, diabetes drugs, MAO inhibitors and corticosteroids. There is an increased risk of bleeding associated with the conjunctive use of licorice and pain relievers, high-blood pressure and blood-thinning medications and drugs used to treat heart conditions, such as digoxin, amiodarone and erythromycin.
Other Safety Considerations
The German Commission E, the European equivalent of the U.S. Food and Drug Administration, suggests limiting licorice supplementation to six weeks, unless otherwise directed by a healthcare practitioner experienced in botanical medicine. However, this herb is not suitable for children or pregnant or lactating women because of the potential hormonal effects. If you have an existing medical condition or take any medications, check with your doctor before using DGL licorice.