Topical β-Caryophyllene for Dermatologic Disorders: Mechanisms, Human Evidence, and Clinical Translation

Background: Chronic inflammatory skin disorders, including atopic dermatitis, psoriasis, acne, and chronic wounds, affect nearly two billion people worldwide, impose substantial morbidity and economic burden, and remain only partially controlled by existing therapies. The cutaneous endocannabinoid system (ECS), comprising cannabinoid receptors, endocannabinoids, and their metabolic enzymes, regulates inflammation, pruritus, barrier integrity, and tissue repair; cannabinoid receptor type 2 (CB2) has emerged as a particularly relevant target. β-Caryophyllene (BCP), a dietary sesquiterpene and highly selective CB2 agonist with favorable safety and pharmacokinetic attributes, has attracted attention as a promising topical candidate. Methods: We systematically searched PubMed, Embase, and Web of Science (inception–30 July 2025) for studies on “β-caryophyllene” and dermatological outcomes, prioritizing purified BCP and analytically characterized BCP-rich fractions. Quantitative parameters, including tested concentration ranges (0.5 µM–10%) and principal mechanistic outcomes, were extracted to provide a translational context. Results: BCP penetrates the stratum corneum, suppresses NF-κB/MAPK and IL-4/TSLP pathways, enhances Nrf2-driven antioxidant defenses, and accelerates re-epithelialization and collagen remodeling. Across in vitro, in vivo, and formulation studies, BCP produced consistent anti-inflammatory and barrier-restorative effects within this concentration range. CB2 antagonism attenuated these responses, confirming receptor specificity. BCP’s volatility and autoxidation to β-caryophyllene oxide (BCPO) necessitate stability-by-design strategies using antioxidants, low-oxygen processing, and protective packaging. Human evidence, limited to BCP-rich botanicals such as Copaifera oleoresins, suggests benefits for scars, wounds, and acne but lacks compound-specific validation. Conclusions: BCP exhibits coherent CB2-mediated anti-inflammatory, antipruritic, antioxidant, and reparative actions with a favorable safety profile. Dose-defined, oxidation-controlled clinical trials of purified BCP are warranted to establish its potential as a steroid-sparing topical therapy.