Transdermal delivery of natural products against atopic dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease. Natural products have been used in AD treatment due to their easy availability, low toxicity, and good pharmacological activities. However, their applications are mainly limited by poor solubility, instability, and permeability. The transdermal drug delivery system (TDDS) provides possibilities for transdermal delivery, penetration promotion, efficacy enhancement, and toxicity reduction of natural drugs to meet the requirements of modern AD treatment. This review introduces the application of hydrogels, microneedles, liposomes, nanoemulsions, and other TDDS carrying natural products in AD treatment, focusing mainly on the effects of natural products' penetration and accumulation in the skin, in order to provide a meaningful program for the treatment of AD and other skin diseases.