Glycyrrhizin an increase in blood pressure, may cause irregular heart rhythm, and adverse interactions with prescription medicines. The effects on body fluids are related to the inhibition of cortisol metabolism within the kidney, subsequent stimulation of the mineralocorticoid receptors, and decrease in blood levels of renin, potassium, and aldosterone, which collectively lead to increases in blood pressure. Depending on amount and frequency of ingesting black licorice, other side effects may include: Glycyrrhizin is under laboratory and preliminary clinical research for its possible activity against common viruses, such as hepatitis C. In vitro, glycyrrhizin inhibits the enzyme 11β-hydroxysteroid dehydrogenase. After oral ingestion,
Glycyrrhizin glycyrrhizin is first hydrolysed to 18β-glycyrrhetinic acid (enoxolone) by intestinal bacteria. After complete absorption from the gut, 18β-glycyrrhetinic acid is metabolised to 3β-monoglucuronyl-18β-glycyrrhetinic acid in the liver. This metabolite then circulates in the bloodstream. Consequently, its oral bioavailability is poor. The main part is eliminated by bile and only a minor part (0.31–0.67%) by urine. After oral ingestion of 600 mg of glycyrrhizin the metabolite appeared in urine after 1.5 to 14 hours. Maximal concentrations (0.49 to 2.69 mg/l) were achieved after 1.5 to 39 hours and metabolite can be detected in the urine after 2 to 4 days. Glycyrrhizin