Herbalist | Chinese Herbal Medicine

Gan Cao, the root of Glycyrrhiza uralensis (Chinese licorice), is called the "harmoniser of all herbs" and appears in more classical formulas than any other single herb. Its name means "sweet herb," reflecting its intensely sweet flavour. In TCM, Gan Cao is classified as sweet in flavour, neutral to slightly warm in temperature (depending on processing), and enters all twelve meridians — a unique characteristic that underlies its harmonising role.

Gan Cao performs five functions: tonifying Spleen Qi (for fatigue and poor appetite), moistening the Lungs and stopping cough (for dry or productive cough), relieving spasms and pain (for muscle cramps, abdominal pain, and spasmodic conditions), clearing heat and resolving toxins (the raw form, Sheng Gan Cao, is used for sore throat, skin sores, and poisoning), and harmonising other herbs in a formula (moderating harsh properties and reducing toxicity of strong herbs). Honey-processed Gan Cao (Zhi Gan Cao) is warmer and more tonifying for the Spleen and Heart.

Despite its gentle reputation, Gan Cao is not without important cautions. Prolonged use in high doses can cause fluid retention and elevated blood pressure due to its glycyrrhizin content, which affects aldosterone metabolism. It should be used cautiously in patients with hypertension, oedema, or hypokalaemia. It is classically incompatible with Hai Zao (Sargassum), Jing Da Ji (Euphorbia pekinensis), Yuan Hua (Daphne), and Gan Sui (Euphorbia kansui) — the so-called "eighteen incompatibilities." Standard dosage is 3 to 9 grams in most formulas, up to 30 grams when used as the primary herb.