Famous for its pungent, sweet flavor, licorice is essential in innumerable candy, confection, beverage and sauce recipes, and makes an estimable liqueur.

Licorice is also a traditional herbal remedy.

The sweet saponin glycyrrhizin occurs in the roots of Glycyrrhiza glabra, the original European source, and in Glycyrrhiza uralensis, Chinese licorice. Authorities treat the two as chemically and medicinally identical. As Grieve puts it, 'The Liquorice of medicine and commerce is derived from the sweet root of various species of Glycyrrhiza, a genus which contains about fourteen species, natives of warmer temperate countries in both the New and Old Worlds...'

The 1997 Commission E on Phytotherapy and Herbal Substances of the German Federal Institute for Drugs recommends Licorice root (Glycyrrhiza glabra) 'For catarrhs of the upper respiratory tract and gastric/duodenal ulcers.'

'Side Effects: On prolonged use and with higher doses, mineralocorticoid effects may occur in the form of sodium and water retention and potassium loss, accompanied by hypertension, edema, and hypokalemia, and, in rare cases, myoglobinuria.'

'Average daily dosage: About 5 - 15 g of root, equivalent to 200 - 600 mg of glycyrrhizin; As Succus liquiritiae: 0.5 - 1 g for catarrhs of the upper respiratory tract, 1.5 - 3 g for gastric/duodenal ulcers;
equivalent preparations.'

'Mode of Administration: Powdered root, finely cut root or dry extracts for infusions, decoctions, liquid or solid dosage forms for internal use (Succus liquiritiae). Duration of Administration: Not longer than 4 - 6 weeks without medical advice. There is no objection to using licorice root as a flavoring agent up to a maximum daily dosage equivalent to 100 mg glycyrrhizin.'

'Actions: According to controlled clinical studies, glycyrrhizic acid and the aglycone of glycyrrhizic acid accelerate the healing of gastric ulcers. Secretolytic and expectorant effects have been confirmed in tests on rabbits. In the isolated rabbit ileum, an antispasmodic action has been observed at concentrations of 1:2500 - 1:5000.'

Although the Commission E lists severe liver disease as a contraindication, less severe liver disease can be helped by the use of licorice. Hepatoprotective licorice tea is widely used as a liver tonic in Japan.

Licorice's triterpene glycyrrhizin has been shown to prevent liver injury from such agents as carbon tetrachloride, benzene hexachloride and PCB. Glycyrrhizin aids antibody production and inhibits the growth of several DNA and RNA viruses, irreversibly inactivating the Herpes simplex virus.

Grieve's classic 'A Modern Herbal': 'The chief constituent of Liquorice root [Glycyrrhiza glabra], to which its sweet taste is due, is Glycyrrhizin (6 to 8 per cent), obtainable in the form of a sweet, white crystalline powder, consisting of the calcium and potassium salts of glycyrrhizic acid. The drug also contains sugar, starch (29 per cent), gum, protein, fat (0.8 per cent), resin, asparagin (2 to 4 per cent), a trace of tannin in the outer bark of the root, yellow colouring matter, and 0.03 of volatile oil.'

'The action of Liquorice is demulcent, moderately pectoral and emollient.'

'It is a popular and well-known remedy for coughs, consumption and chest complaints generally, notably bronchitis, and is an ingredient in almost all popular cough medicines on account of its valuable soothing properties.'

'The Extract enters into the composition of cough lozenges and pastilles, with sedatives and expectorants. It is largely used in conjunction with infusion of linseed in the treatment of irritable cough, sore throat and laryngitis, and an infusion made by boiling 1 oz. of the bruised root deprived of its bark, with 1 pint of water for a few minutes, may be employed in the treatment of sore throat and in catarrhal conditions of the urinary intestinal tracts.'

'Fluid Extract of Liquorice is employed almost exclusively as a vehicle for disguising the taste of nauseous medicines, having a remarkable power of converting the flavour of acrid or bitter drugs, such as Mezereon, Quinine or Cascara.'

'The powdered root is useful in pill-making on account of its absorbent qualities, being used to impart stiffness to pill masses and to prevent the adhesion of pills.'

'As a remedial agent, powdered Liquorice root has been almost entirely replaced by the extract, though it is used in the well-known Compound Liquorice Powder, the mild laxative in which Senna and Fennel are the other ingredients. It is added mainly on account of its sweetness and emollient qualities, the action of the powder being mainly due to the Senna contained.'

'The sugar of Liquorice may safely be taken by diabetic patients.'

'On the whole, Liquorice as a domestic medicine is far more largely used on the Continent than in Great Britain. It is much used in China and largely produced (both G. glabra and G. echinata) in some of the northern provinces, a variety of medicinal preparations being employed, not only as possessing tonic, alterative and expectorant properties, but also for the rejuvenating and highly nutritive qualities attributed to it.'

'Preparations and Dosages: Powdered root, ½ to 1 drachm. Fluid extract, 1 to 4 drachms. Comp. powder, B.P., 1 to 2 drachms. Solid extract, 1 drachm. Comp. lozenges, U.S.P. Solid extract in stick form, known as Liquorice Juice.'

'Liquorice is also largely used by brewers, being added to porter and stout to give thickness and blackness.'

American Materia Medica, 1919 (Ellingwood): 'The agreeable taste of liquorice in any form covers to a practical extent the taste of very many disagreeable remedies. Acrid and bitter tastes are well disguised by it. A syrup made by adding two parts of the fluid extract to fourteen parts of simple syrup, will disguise the bitter or otherwise unpleasant taste of a large proportion of the fluid extracts. The taste of quinine can be concealed by it to a considerable extent.'

'Its demulcent properties render it useful in inflammation, or irritation of the mucous membranes of the lungs and bronchi. In combination with ipecac, lobelia, squill, sanguinaria, or ammonium chloride, an excellent expectorant mixture or cough syrup may be extemporized, as this agent modifies any acrid or irritating influence the other agents may exhibit.'