Glycyrrhetinic Acid and its salts and esters and Glycyrrhizic Acid and its salts and esters are cosmetic ingredients that function as flavoring agents or skin-conditioning agents - miscellaneous or both. These chemicals may be isolated from licorice plants. Glycyrrhetinc Acid is described as at least 98% pure, with 0.6% 24-OH-Glycyrrhetinic Acid, not more than 20 mu g/g of heavy metals and not more than 2 mu g/g of arsenic. Ammonium Glycyrrhizate has been found to be at least 98% pure and Dipotassium Glycyrrhizate has been found to be at least 95% pure. Glycyrrhetinic Acid is used in cosmetics at concentrations of up to 2%; Stearyl Glycyrrhetinate, up to 1%; Glycyrrhizic Acid, up to 0.1%; Ammonium Glycyrrhizate, up to 5%; Dipotassium Glycyrrhizate, up to 1%; and Potassium Glycyrretinate, up to 1%. Although Glycyrrhizic Acid is poorly absorbed by the intestinal tract, it may be hydrolyzed to Glycyrrhetinic Acid by a beta -glucuronidase produced by intestinal bacteria. Glycyrrhetinic Acid and Glycyrrhizic Acid bind to rat and human albumin, but do not absorb well into tissues. Glycyrrhetinic Acid and Glycyrrhizic Acid and metabolites are mostly excreted in the bile, with very little excreted in urine. Dipotassium Glycyrrhizate was undetectable in the receptor chamber when tested for transepidermal permeation through pig skin. Glycyrrhizic Acid increased the dermal penetration of diclofenac sodium in rat skin. Dipotassium Glycyrrhizate increased the intestinal absorption of calcitonin in rats. In humans, Glycyrrhetinic Acid potentiated the effects of hydrocortisone in the skin. Moderate chronic or high acute exposure to Glycyrrhizic Acid, Ammonium Glycyrrhizate, and their metabolites have been demonstrated to cause transient systemic alterations, including increased potassium excretion, sodium and water retention, body weight gain, alkalosis, suppression of the renin-angiotensis-aldosterone system, hypertension, and muscular paralysis; possibly through inhibition of 11beta -hydroxysteroid dehydrogenase-2 (11beta -OHSD2) in the kidney. Glycyrrhetinic Acid and its derivatives block gap junction intracellular communication in a dose-dependent manner in animal and human cells, including epithelial cells, fibroblasts, osteoblasts, hepatocytes, and astrocytes; at high concentrations, it is cytotoxic. Glycyrrhetinic Acid and Glycyrrhizic Acid protect liver tissue from carbon tetrachloride. Glycyrrhizic Acid has been used to treat chronic hepatitis, inhibiting the penetration of the hepatitis A virus into hepatocytes. Glycyrrhetinic Acid and Glycyrrhizic Acid have anti-inflammatory effects in rats and mice. The acute intraperitoneal LD(50) for Glycyrrhetinic Acid in mice was 308 mg/kg and the oral LD(50) was > 610 mg/kg. The oral LD(50) in rats was reported to be 610 mg/kg. Higher LD(50) values were generally reported for salts. Little short-term, subchronic, or chronic toxicity was seen in rats given ammonium, dipotassium, or disodium salts of Glycyrrhizic Acid. Glycyrrhetinic Acid was not irritating to shaved rabbit skin,...