Allergies and Asthma. Licorice contains glycyrrhizin, a substance known to exert anti-inflammatory and antiallergenic properties. This agent inhibits the manufacture of proinflammatory prostaglandins and leukotrienes, which are linked to allergic and asthmatic symptoms.
Ulcers. Licorice has been shown to be very effective at treating and preventing ulcers. However, since the component glycyrrhizin has the ability to raise blood pressure, it is wise to use deglycyrrhizinated licorice (DGL) when treating ulcers. In research studies, DGL has been shown to be more effective at treating ulcers than several prescription ulcer medications. In one con-trolled study, 33 gastric ulcer patients were treated with either 760 mg DGL or placebo three times daily for one month. Results showed 75 percent of the DGL group had a significant reduction in ulcer size, compared to 34 percent in the placebo group.
Hepatitis. In a Japanese study, chronic hepatitis C patients received glycyrrhizin intravenously, along with the amino acids cysteine and glycine. The study found that the intravenous solution helped lower liver enzyme levels and prevent progression to liver cancer. Another Japanese study concluded that combination therapy using glycyrrhizin and ursodeoxycholic acid improved liver enzyme levels and may be an alternative to interferon treatment for people with chronic hepatitis C.
Eczema. Licorice’s benefits for eczema and other skin conditions can be exerted both internally and externally. When taken internally, licorice can produce anti-inflammatory and antiallergenic effects. As a topical agent, licorice gel containing pure glycyrrhetinic acid has demonstrated the ability to exert healing effects similar to hydrocortisone products.
High doses of licorice containing glycyrrhizin can cause sodium and water retention, reduced potassium levels, and increases in blood pressure. People with kidney failure, hypokalemia (i.e., low potassium levels in the blood), and high blood pressure should avoid taking licorice root. Pregnant women and people with cardiac arrhythmias also should avoid licorice.
A general dose for glycyrrhizin-containing licorice is 5 to 6 grams per day in capsule form, or 250 to 500 mg three times per day in concentrated extract. When using DGL for ulcers or digestive tract conditions, 2 to 4 200-to-300-mg tablets should be chewed three times per day before meals and before going to bed.