Common Licorice root is a well-known herb primarily used as a harmonizer in Chinese herbal formulas. It has been employed as medicine in China for at least 2,000 years. Modern science has shown Licorice to have value as an anti-inflammatory^1,2,3,4 and anti-microbial^5,6,7 agent. It has also been shown to reduce itching⁸  in atopic dermatitis.

References:

1. Schrofelbauer, B. et al., Glycyrrhizin, the main active compound in liquorice, attenuates pro-inflammatory responses by interfering with membrane-dependent receptor signaling. Biochem J. 2009. 421(3):473-82.
2. Azimov, MM. et al., Pharmacological study of the anti-inflammatory agent glyderinine. Farmakol Toksikol. 1988. 51(4):90-3.
3. Kim KR, et al. Anti-inflammatory effects of licorice and roasted licorice extracts on TPA-induced acute inflammation and collagen-induced arthritis in mice. J Biomed Biotechnol. 2010;2010:709378.
4. Matsui S, et al. Glycyrrhizin and related compounds down-regulate production of inflammatory chemokines IL-8 and eotaxin 1 in a human lung fibroblast cell line. Int Immunopharmacol. 2004 Dec 15;4(13):1633-44.
5. Krausser, R. et al., In vitro anti-Helicobacter pylori activity of Extractum liquiritiae, glycyrrhizin and its metabolites. J Antimicrob Chemother. 2004, 54(1):243-6..
6. Li, J. et al., Comparative analysis of the effect of glycyrrhizin diammonium and lithium chloride on infectious bronchitis virus infection in vitro. Avian Pathol. 2009, 38(3):215-21.
7. Hatano T, Kusuda M, Inada K et al. 2005. Effects of tannins and related polyphenols on methicillin-resistant Staphylococcus aureus. Phytochemistry 66: 2047–2055.