Traditional use
Traditionally used in Chinese medicine as a harmonizer that rounds off harsh formulas, and in Western herbal practice for cough and digestive comfort. In the TCM kitchen it is the peacemaker — a few slices in a formula so the louder herbs go down easier; European practice simmers the root into cough syrups and throat lozenges. Folk colour: the sweetness is natural and ancient — confectioners copied it for centuries. In the TCM kitchen it is the peacemaker — a few slices in a formula so the louder herbs go down easier; European practice simmers the root into cough syrups and throat lozenges. Modern preparations include the dried root slices for decoction (the TCM form), the powdered root, and the deglycyrrhizinated (DGL) form used for digestive comfort. Species differ: Western products are usually Glycyrrhiza glabra, while TCM Gan Cao is G. uralensis. The deglycyrrhizinated form lacks the glycyrrhizin-driven blood-pressure concerns, while the whole root retains them.
How it’s traditionally used
In Chinese apothecaries and clinic pharmacies you'll meet it most often as thin dried slices or rings of root — boiled for twenty or thirty minutes in a clay pot, often with a few jujubes and a couple of slices of fresh ginger to soften the sweetness. The decoction is rarely drunk on its own, and instead shows up as the harmonizer inside classical formulas, the last herb added to round the blend. Across European herbal shops the same root appears as coarse powder for tea, a thick dark syrup sold in small bottles, and tincture taken by the dropper. The Pontefract cakes of northern England began life as an apothecary preparation, long before confectioners took the recipe over. In Korean and Japanese households the dried slices turn up in winter broths, simmered alongside chicken or beef ribs. Across these traditions licorice is a kitchen-and-apothecary companion used across weeks of a season, not a one-night rescue.
What research says so far
Has been studied for digestive comfort and cough; evidence is limited, and glycyrrhizin-containing preparations measurably raise blood pressure and lower potassium in recent trials. The modern concern is concrete: controlled work shows everyday amounts of glycyrrhizin can nudge blood pressure up and potassium down within weeks — which is why deglycyrrhizinated forms exist at all. Human trials enrol 30 to 200 participants over 4 to 12 weeks; common outcomes include cough-frequency scores in upper-respiratory infection studies, digestive-comfort questionnaires in functional dyspepsia trials, and blood pressure plus serum potassium in controlled metabolic studies. The glycyrrhizin safety story is well documented: controlled studies show everyday amounts raise blood pressure and lower potassium within weeks in susceptible people — which is why deglycyrrhizinated forms exist at all. Cough-syrup trials report modest symptom reductions; digestive-comfort trials are mixed. The trial literature is well-developed for the safety side, less so for the symptom-relief claims.
Things to be careful about
Commonly used amounts in traditional practice vary by preparation. Safety comes first with licorice: glycyrrhizin-containing forms can raise blood pressure and lower potassium even at everyday amounts, so avoid during pregnancy and breastfeeding, and skip if you have high blood pressure, heart disease, or kidney problems. Do not combine with diuretics (potassium loss worsens) or cardiac glycosides (effects amplify); consult a clinician if you take any medication. Watch for swelling, muscle pain, irregular heartbeat, or unusual bruising or bleeding, and stop if these appear. Deglycyrrhizinated (DGL) forms do not carry these risks. Liver injury has not been reported. Species differ: Western products are usually G. glabra, while TCM Gan Cao is G. uralensis.
