glycyrrhizin as a potential treatment for chronic hepatitis C

Chronic hepatitis C is a slowly progressive liver disease that may evolve into cirrhosis with its potential complications of liver failure or hepatocellular carcinoma. Current therapy with α‐interferon is directed at viral clearance, but sustained response is only achieved in 20–40% of patients without cirrhosis, and less than 20% in patients with cirrhosis who have the greatest need for therapy. Treatment for those who do not respond to anti‐viral therapy is highly desirable. In Japan glycyrrhizin has been used for more than 20 years as treatment for chronic hepatitis. In randomized controlled trials, glycyrrhizin induced a significant reduction of serum aminotransferases and an improvement in liver histology compared to placebo. Recently, these short‐term effects have been amplified by a well‐conducted retrospective study suggesting that long‐term usage of glycyrrhizin prevents development of hepatocellular carcinoma in chronic hepatitis C. The mechanism by which glycyrrhizin improves liver biochemistry and histology are undefined. Metabolism, pharmacokinetics, side‐effects, and anti‐viral and hepatoprotective effects of glycyrrhizin are discussed.