Advances in Dermal Drug Delivery Formulation Approaches to Enhance Dermal Delivery of Centella asiatica Extract and Asiatic Acid: A Systematic Narrative Review

Abstract

Centella asiatica, is a medicinal plant that exhibits a wide range of pharmacological activities, particularly in inflammatory and skin-related diseases. One of its major bioactive compounds is asiatic acid. However, its application as a topical formulation is often limited by unfavorable physicochemical properties, which hinder its penetration through the skin. This systematic review aimed to evaluate pharmaceutical formulation strategies that can enhance the dermal delivery of C. asiatica extract and asiatic acid. The literature search followed PRISMA guidelines with predefined inclusion and exclusion criteria. A total of 49 articles were identified, of which 11 met the eligibility criteria and were included in this review. The findings indicate that vesicle and nanocarrier-based delivery systems, such as ethosomes, transfersomes, liposomes, and nanostructured lipid carriers, are effective in improving the dermal delivery of C.asiatica extract by enhancing solubility, vesicle deformability, and interactions with skin lipids. Meanwhile, formulation approach for asiatic acid are generally aimed at improving its solubility and modifying the stratum corneum barrier using chemical penetration enhancers or flexible carrier systems such as transfersomes. Overall, these approaches highlight that formulation design plays a crucial role in enhancing the dermal delivery of C. asiatica extract and asiatic acid.