Licorice root (Glycyrrhiza glabra) has been used since ancient times, yet licorice root side effects can be dangerous and are important to understand before taking this herbal preparation. Side effects may include serious complications such as high blood pressure or cardiac problems.
About Licorice Root
The first mention of licorice root occurs in Egyptian texts. Egyptian priests offered libations of licorice root to honor the spirits of departed pharaohs. In ancient Greece, preparations of licorice root were used medicinally for upper respiratory, liver and stomach ailments. Licorice is also very sweet, and extracts were used throughout history to sweeten foods and beverages. Licorice candy demonstrates the sweet flavor, but oddly enough, most commercially prepared licorice candy today uses another herb, anise, for the flavor. Licorice is used today to sweeten herbal lozenges, cough drops and even some tobacco products, although the amount found in these products is so small it is unlikely to cause any side effects.
Licorice Root Side Effects
Although herbalists and naturopathic doctors may recommend taking licorice root for a variety of ailments, it is an herb that may cause potentially dangerous side effects. Pure licorice root contains glycyrrhizic acid, which is the culprit behind most side effects. Some herbal products deglycyrrhizinated the licorice, or remove the acids that cause many side effects. Look for the abbreviation DGL on the label to indicate deglycyrrhizinated licorice. It's considered safer to use, although not 'safe.' Always follow the label directions on herbal products and consult a qualified herbalist for the proper dose. Tell your doctor about any herbal products including licorice that you are taking. The National Center for Complementary and Integrative Medicine (NIH) lists the following side effects.
Some people are allergic to licorice root. Licorice is actually related to the pea family, so if you know you are allergic to any legumes or peas, avoid taking licorice.
Electrolyte and Chemical Imbalances
Licorice acts upon the hormones and chemicals in the body, and may disrupt the body's delicate balance. This can lead to electrolyte imbalances, such as too little potassium and too much salt retained in the body. A potassium and sodium imbalance can lead to muscle cramps, heart problems or high blood pressure.
Another side effect reported from licorice root extract is reduced testosterone in men and increased levels of prolactin and estrogen in women. These may causes changes in sexual desire or symptoms related to the reproductive organs.
Changes in Weight
Both weight gain and weight loss have been reported as a side effect of licorice root. Weight is influenced by hormones that regulate appetite; it is possible that the hormonal imbalances caused by licorice root affect the hormones related to appetite and metabolism, but researchers aren't entirely sure why some people gain and others lose weight while taking licorice root.
Vision problems including blurry vision or loss of vision have been reported among people taking licorice root extract. Sometimes this is caused by dangerously high blood pressure associated with taking licorice root.
Licorice should never be taken during pregnancy or while a woman is trying to become pregnant. It has too many known effects upon hormones, which can all affect fertility and the health of both mother and child. Anyone with high blood pressure should avoid licorice root altogether. Licorice root interacts badly with diuretic medications, blood pressure medications, insulin, steroid medications and MAO (monoamine oxidase inhibitors). Licorice root side effects may be serious. Do not take licorice root if you take any of these medications or others listed on Medline Plus or other reputable sources of information.