This root has been used for centuries in many parts of the world. An NCCAM review of randomized, controlled studies using injectable licorice extract reports possible benefits for improvement of liver tissue for hepatitis patients and may reduce HCV complications for non-responders to interferon treatment. Research did not support the notion that licorice root prevents liver cancer in those with HCV.
Glycyrrhizin may lower liver enzymes but does not seem to lower HCV viral loads. May be an effective treatment for upset stomachs. Purported to stimulate the adrenal glands and prevent ulcers related to aspirin or NSAID use, but the evidence is insufficient.
Attention for Liver Disease: In spite of the NCCAM review, those with liver disease should use cautiously until safety and efficacy have been well established. Should be avoided by anyone with cirrhosis or cholestatic liver disorders. May worsen ascites. May lower liver enzymes. Because it appears to interact with cytochrome P-450 metabolized substances (see Cytochrome P-450), do not take licorice during HCV treatment.
Safety Information: Likely safe when used in moderate amounts. Glycyrrhizin is the primary active substance in licorice root, and may have the most potential to harm; deglycyrrhizinated licorice is safer, but may no t be effective. However, efficacy hasn’t been established in either form of licorice. Prolonged or excessive use can lead to potentially serious side effects including, potassium depletion, high blood pressure, lethargy, hypertensive encephalopathy, sodium and water retention and swelling. Should be avoided by anyone with kidney disease, diabetes, and hormone-sensitive cancer. Other potential side effects include nausea, vomiting, headache, and decreased libido in men. Should be avoided by pregnant and nursing women. Safety in children is not established.
Interactions: May interact with diuretics, digitalis, antiarrhythmics, corticosteroids, heart and blood pressure medications, MAO inhibitors, antidiabetes drugs, anti-rejection agents, hormones, birth-control pills and anti- cancer drugs such as tamoxifen. May interact with any cytochrome P-450 metabolized substances (see Cytochrome P-450).
Interactions: May interact with diuretics, digitalis, antiarrhythmics, corticosteroids, heart and blood pressure medications, MAO inhibitors, antidiabetes drugs, anti-rejection agents, hormones, birth-control pills and anti- cancer drugs such as tamoxifen.
Lab Notes: May decrease liver enzymes, potassium and testosterone levels. May increase sodium levels and blood pressure. May alter blood glucose levels.
Note: Licorice root should not be used for more than 4 to 6 weeks. Prolonged use increases risk of serious side effects. Some sources recommend use of deglycyrrhizinated (DGL), since glycyrrhizic acid may be responsible for most of the side effects. However, some argue that this reduces overall effectiveness.