Licorice Root
Glycyrrhiza glabra
Also known as: Sweet Root, Mulethi, Yashtimadhu
Overview
A foundational herb in Ayurvedic, TCM, and Western herbalism. Human trials support two narrow uses: in one randomized trial, licorice added to standard antibiotic therapy improved H. pylori eradication (83% vs 63%), and in several trials a licorice gargle before surgery cut post-operative sore throat and cough roughly in half. Its wider reputation for healing the gut, lungs, and adrenals runs well ahead of that evidence — and the adrenal part has it backwards: glycyrrhizin, licorice's main active compound, blocks the enzyme that clears cortisol, and the buildup can raise blood pressure and lower potassium even at modest daily amounts. Use short-term and with medical guidance, especially with high blood pressure, heart or kidney conditions, or diuretic and blood-pressure medications. Deglycyrrhizinated licorice (DGL) has that compound removed and does not carry this risk.
Proposed mechanism
Gut microflora convert glycyrrhizin into glycyrrhetinic acid, which inhibits 11β-HSD2 — the enzyme that normally inactivates cortisol — raising cortisol activity in nearby tissue. On skin, that is the accepted explanation for the improvement seen with topical licorice gel in small vehicle-controlled eczema trials. Taken by mouth, the same enzyme block is the established cause of licorice-induced pseudoaldosteronism — fluid retention, potassium loss, and rising blood pressure — with risk climbing with dose and duration and varying widely between individuals, so oral licorice root is not a dependable anti-inflammatory route and warrants caution for anyone with high blood pressure, heart or kidney disease, or taking diuretics. Deglycyrrhizinated licorice (DGL) has the glycyrrhizin removed and does not carry this effect. Glycyrrhizinic acid inhibits thrombin and phospholipase A2 in laboratory studies. The demulcent action is best supported in the throat, where a 70-trial network meta-analysis ranked licorice gargle among the most effective agents against post-intubation sore throat; controlled trials of DGL in gastric ulcer have found no healing benefit over placebo.
Mechanisms describe how researchers think a compound may act, often from laboratory work — a proposed mechanism is not proof of a clinical effect in people.
Traditional & studied uses
Related pathways
Pathway tags are a research aid for browsing the glossary — they are not a claim that this ingredient treats any condition.