In ancient China, licorice was considered a principle drug among all drugs. It is perhaps the most commonly used herb in classical prescriptions. [The Shennong Herbal] states that licorice is used to balance the five viscera (organs) and six bowels. It also reports that licorice strengthens the sinews and bones, enhances muscle growth and strength, and is used topically to heal wounds.
Liquorice root is emollient, demulcent, and nutritive. It acts upon mucous surfaces, lessening irritation, and is consequently useful in coughs, catarrhs, irritation of the urinary organs, and pain of the intestines in diarrhoea.
Licorice is broadly antiviral. It is active against a wide range of viruses through multiple mechanisms. It strongly inhibits the ability of many viruses to create the membrane pores through which the viruses then enter cells. This slows or even ends the viral infection right there. For other viruses, it is directly virucidal, and for others it stimulates the host immune system specifically to attack the invading virus.
As an adaptogen, licorice benefits the HPA axis function and the sympathoadrenal system (SAS). I frequently use it for people with adrenal insufficiency who have symptoms of fatigue, tiredness upon waking up in the morning, elevated cortisol and blood sugar levels, and frequent colds.
Licorice is used in Ayurveda to improve eyesight, strength, sexual potency and libido. Licorice is considered, as adaptogens generally do, to enhance the effects of other herbs in a formula,so it is widely used.