Herb library · Herb · Glycyrrhiza glabra, G. uralensis, G. inflata
Licorice Root
A sweet root used as a flavoring and sold for digestive, respiratory, and energy support. No high-quality evidence clearly supports it for any condition, and its glycyrrhizin can seriously affect the heart in large amounts or with long use.
Serious warning
Licorice contains glycyrrhizin, which NCCIH says can cause serious adverse effects such as irregular heartbeat and cardiac arrest, especially in large amounts or with long-term use. Even small amounts have been linked to severe effects in people with high blood pressure, heart or kidney conditions, or a high-salt diet.
Traditional use
Licorice root has a long history in ancient Assyrian, Egyptian, Greek, Arab, Chinese, Tibetan, and Indian cultures, used for coughing, asthma, and wounds, and for diseases of the lungs, liver, and arteries. It flavors candy, other foods, and tobacco. Many "licorice" products sold in the United States contain anise oil instead. Today it is sold for digestive, respiratory, and energy support, and on the skin for some skin conditions.
Traditional energetics
Galenic (hot or cold, dry or moist)
Hot and moist. Culpeper's Complete Herbal (1814), p. 222 (opens in a new tab)
What studies show
- Limited
Canker sores: a licorice mouth rinse or gargle might reduce ulcer size and pain, and topical licorice might reduce ulcer size. In one study licorice plus a standard canker sore medicine did better than the medicine alone.
- Limited
Sore throat after surgery: a licorice gargle or lozenge before surgery might lessen sore throat after intubation.
- Limited
Eczema and burns: preliminary evidence suggests topical licorice gels might help; more research is needed on effects and safety.
- Insufficient
Bad breath: one preliminary study found a licorice mouthwash might help.
- Insufficient
Digestive symptoms: it is unclear whether licorice alone (not in herbal blends) has any effect. There is no good evidence for COVID-19.
Be careful of
Cautions
- NoteLicorice is generally considered safe as a food ingredient. Products with the glycyrrhizin removed (deglycyrrhizinated licorice, DGL) might be safe for up to 4 months.
- InteractionInteractions between licorice and corticosteroids have been reported.
- NoteTopical licorice may be safe short term but can irritate the skin.
- PregnancyLarge amounts of licorice (about 250 grams a week) in pregnancy are unsafe and can raise the chance of delivery before 38 weeks. Little is known about breastfeeding.
- Ask a clinicianTalk with a clinician or pharmacist before using this if you take prescription medicines, are pregnant or breastfeeding, or are giving it to a child.
From the old books
What herbals and dispensaries of the past printed. History, in their words.
“The bitterness of quinine, quassia, aloes, and the acrid taste of senega, guaiacum, mezereon and ammonium chloride are masked by liquorice.”
Sources
- Licorice Root: Usefulness and Safety (opens in a new tab) · NCCIH · read September 25, 2026
- Licorice (LiverTox) (opens in a new tab) · NIH · read September 25, 2026
Reviewed September 25, 2026.