Advanced delivery of natural bioactive compounds for atopic dermatitis: a review of polymeric conjugates and nanocarriers

Atopic dermatitis (AD) is a persistent, relapsing skin inflammatory disorder characterised by epidermal barrier dysfunction, immune system anomalies, and microbial dysbiosis. Current therapies encompass calcineurin inhibitors, topical corticosteroids, and synthetic drugs such as JAK inhibitors and biologics, which, despite their efficacy, have safety issues and constraints on prolonged use. Recently, natural bioactive compounds namely flavonoids, polyphenols, and terpenoids have garnered interest for their anti-inflammatory, antioxidant, and skin-barrier-repairing characteristics. Recent studies emphasise the incorporation of these bioactive compounds into hydrophilic/hydrophobic polymeric conjugates and nanocarrier systems to promote skin distribution, increase efficacy, and minimise systemic adverse effects. This study encapsulates traditional and innovative medicines, highlights the promise of polymer-conjugated herbal formulations, and examines recent developments in nanotechnology and delivery technologies for AD management. The increasing interest in bioactive ingredient formulations and polymeric nanocarriers indicates a favourable shift towards safer, more effective, and patient-compliant treatment methodologies.