Glycyrrhizin, a major bioactive compound found in licorice root (Glycyrrhiza glabra), has been investigated for its potential therapeutic effects in inflammatory skin disorders, including psoriasis. Evidence supporting its use in psoriasis comes primarily from preclinical studies and a limited number of small clinical trials. Glycyrrhizin exhibits anti-inflammatory, immunomodulatory, and antioxidant properties, which are relevant to the pathophysiology of psoriasis—a chronic autoimmune disease characterized by hyperproliferation of keratinocytes and inflammation.

Laboratory studies have demonstrated that glycyrrhizin can inhibit the production of pro-inflammatory cytokines such as TNF-α, IL-6, and IL-17, all of which play key roles in psoriasis. Additionally, glycyrrhizin has been shown to suppress NF-κB activation, a signaling pathway central to the inflammatory response in psoriatic lesions. Some animal studies and in vitro experiments have also indicated that glycyrrhizin can reduce keratinocyte proliferation and oxidative stress.

However, high-quality human studies are scarce. A few small clinical studies have reported improvements in psoriatic symptoms with topical or oral glycyrrhizin, but larger randomized controlled trials are lacking. Therefore, while there is a scientific rationale and preliminary evidence for glycyrrhizin’s use in psoriasis, the overall level of evidence is limited, and more robust clinical research is needed to confirm its efficacy and safety for this indication.