Native to southern Europe and central Asia, the licorice (Glycyrrhiza glabra) plant has been part of traditional Chinese medicine for centuries. Licorice root contains coumarins, flavonoids, glycyrrhizin, phytoestrogens, plant sterols and volatile oils--chemical compounds believed to hold medicinal properties. Glycyrrhizin is thought to boast the most healing properties, as it has the ability to decrease inflammation, relieve irritation, safeguard the gastrointestinal tract and encourage the discharge of mucous. Licorice root is thought to be effective in treating a range of ailments, such as coughs, sore throats, food poisoning, digestive and urinary tract infections and disorders of the liver and stomach. That being said, licorice root is also attributed with a number of side effects


Licorice root supplements are available in two different forms: the standard form which includes glycyrrhizin, and the other that contains no glycyrrhizin (deglycyrrhizinated licorice, or DGL). The standard form is primarily used to treat respiratory infections, whereas the other is employed to treat digestive tract conditions. When taken in large dosages, the supplement containing glycyrrhizin can trigger an increase in blood pressure, decrease in potassium level and cause a person to retain excessive amounts of salt and water, potentially resulting in heart problems. The glycyrrhizin-free supplements are considered to produce a smaller number of side effects.

Preexisting Conditions

Licorice root is not advised for people with certain preexisting medical conditions. Those with diabetes, high blood pressure, hypertension, fluid retention problems, low potassium blood levels, glaucoma, heart, kidney, liver and thyroid disease should avoid the herb. Since licorice root can also facilitate the conversion of testosterone into estrogen, people with particular hormonal conditions (fibrocystic breasts, breast or uterine cancer) are directed to avoid licorice root. Additionally, licorice root can decrease testosterone levels, so men who are infertile or suffer from erectile dysfunction should steer clear of it as well.

Dosage Issues

Exceeding the recommended dose of licorice root can be harmful to a person's health. Frequently consuming licorice dosages higher than advised can result in elevated blood levels of the aldosterone hormone, causing side effects of headache, high blood pressure and heart complications. Taking large amounts of the root's component glycyrrhizin can lead to pseudoaldosteronism, a condition that affects a hormone within the adrenal cortex and results in fatigue, increased pressure, migraines, water retention, swelling of the limbs and risk of heart attack. Though the most hazardous side effects are usually attributed to elevated doses of licorice or glycyrrhizin, unfavorable consequences can also occur on therapeutic dosages. Headache, facial puffiness, fatigue, leg swelling, visual disturbances and weakness are signs of an adverse reaction or overdose.

Drug Interactions

Like other supplements, licorice root can interfere with the effectiveness, potency and components of other medications and remedies, including over-the-counter medications, vitamins and herbs. Inform your doctor of any medications you are on or have recently stopped using. This is especially important for those on ACE-inhibitors, diuretics, aspirin, corticosteroids, digoxin, hormone replacements, insulin, laxatives and oral contraceptives.


Women who are pregnant, plan on becoming pregnant or breast feeding should avoid licorice root because of the potential side effects. It's worth noting that the precautions concerning licorice root and its side effects pertain to every form or source that it comes in, which includes capsules, dried herbs, lozenges, tablets and tinctures. Furthermore, licorice root and like products are not to be taken for a period exceeding 4 to 6 weeks unless otherwise determined by a doctor.

About the Author

Serena Spinello

Serena Spinello holds two master’s degrees and is pursuing her Ph.D. in medical science. She has been a professional writer and researcher for over 10 years and is an active member of the American Medical Writers Association, Academy of Medical Educators, and the National Association of Social Workers.