Caffeic acid and its analogs are phenolic compounds found in many plants and foods, and they have been investigated for their antioxidant, anti-inflammatory, and immunomodulatory properties. Scientific interest in their use for psoriasis stems from preclinical studies demonstrating that caffeic acid can modulate inflammatory pathways, such as inhibiting NF-κB activation and reducing the expression of pro-inflammatory cytokines (e.g., TNF-α, IL-17, IL-23), which are implicated in the pathogenesis of psoriasis. Animal models of psoriasis-like skin inflammation have shown that topical or systemic administration of caffeic acid or some of its analogs can ameliorate symptoms by reducing skin thickness, scaling, and inflammatory cell infiltration.

However, evidence in humans is very limited. Most of the research has been conducted in vitro or in animal models. There are very few, if any, clinical trials directly evaluating caffeic acid analogs for psoriasis in humans. As such, while there is a scientific basis for further investigation and some preliminary preclinical evidence, the overall strength of evidence is low, and caffeic acid analogs are not part of standard dermatological treatment for psoriasis. More robust clinical studies are needed to validate their efficacy and safety in human subjects.