Caryophyllene, specifically β-caryophyllene, is a natural bicyclic sesquiterpene found in many essential oils, such as clove oil and cannabis. Its use for eczema (atopic dermatitis) is supported by some preclinical scientific evidence, though robust human clinical trials are lacking. Research has shown that β-caryophyllene acts as a selective agonist of the cannabinoid receptor type 2 (CB2), which is involved in modulating inflammation and immune responses. In animal models, topical application of β-caryophyllene reduced inflammation and improved skin barrier function. For example, a 2014 study in mice demonstrated that β-caryophyllene suppressed allergic inflammatory responses in a model of contact dermatitis, suggesting potential benefits for eczematous conditions (Physiology & Behavior, 2014). Another study found that its CB2 activity contributed to reduced skin inflammation and promoted wound healing (PLoS ONE, 2014).

However, direct evidence from human trials is currently absent. Most of the available data come from cell culture or animal studies, indicating promise but not establishing clear efficacy or safety in humans with eczema. Thus, while there is a plausible scientific mechanism and some preliminary supporting data, the overall level of evidence is low to moderate pending further research.