Glycyrrhizin (licorice root extract) is extracted from the roots of the plant Glycyrrhiza glabra. Evidence of licorice root has been found in Egyptian tombs, and writings through the ages have described its use in suppressing cough, and soothing sore throats and upset stomachs. Because it is 50x sweeter than sucrose, its traditional use was as a sweetener of food and medications. A typical preparation contains between 5 and 25% percent of the product as glycyrrhizin. Reported healing properties include a reduction in inflammation via vasoconstriction, inhibition of inflammatory cell migration within tissues, and perhaps antiviral activities against a variety of viral agents, that may result from the induction of IFN-y.
One trial (20), which evaluated a glycyrrhizin-based compound against "other herbs," included 193 hepatitis C patients, followed prospectively for 2-16 yr for evidence of progression to cirrhosis or the development of hepatocellular carcinoma. Although glycyrrhizin appeared to slow the histological progression of the disease, both groups appeared to progress to carcinoma more frequently than in similar patients treated with IFN. Side effects attributed to glycyrrhizin included hypokalemia in 11% and hypertension (HT) in 3.6%. In a single randomized control study of iv glycyrrhizin vs placebo, among 58 IFN nonresponders or patients unlikely to respond (cirrhotic patients with genotype 1), the herb resulted in lower ALT, with no effect on HCV RNA levels (21). The adverse effects of glycyrrhizin in humans are well-characterized. Glycyrrhizin inhibits 11-^-hydroxysteroid hydrogenase in the kidney, inhibiting the conversion of cortisol to cortisone. This results in a pseudohyper-aldosteronism, leading to development of HT, hypokalemia, peripheral edema, headache, and metabolic alkalosis, especially if high doses of glycyrrhizin are administered. This has led to the recommendation that patients at risk for portal HT should avoid glycyrrhizin-based products, because of concerns of volume retention, and exacerbation of portal HT.
Was this article helpful?