Baicalin, a flavonoid derived from the root of Scutellaria baicalensis (Chinese skullcap), has been investigated for its anti-inflammatory and immunomodulatory properties, which are relevant to the pathogenesis of psoriasis. Laboratory studies have demonstrated that baicalin can inhibit the proliferation of keratinocytes and reduce the expression of inflammatory cytokines such as TNF-α, IL-6, and IL-17, which are implicated in psoriatic lesions. For instance, several in vitro studies and animal models (such as imiquimod-induced psoriasis-like mice) have shown that baicalin administration leads to an improvement in skin lesion severity and modulation of Th17 and regulatory T cell responses.

However, clinical evidence in humans is limited. A few small-scale clinical trials and case reports from China suggest potential benefits when baicalin-containing formulations are used topically or orally, but these studies often lack rigorous controls, have small sample sizes, or are published in non-English journals, making it difficult to generalize the findings. No large, high-quality randomized controlled trials have been conducted to definitively establish efficacy or safety profiles in human psoriasis patients. As such, while there is a scientific rationale and early preclinical evidence supporting baicalin’s use for psoriasis, the overall evidence strength remains modest, justifying a rating of 2 out of 5.