Topical Drug Delivery using Self-Emulsifying Nanolipidic Systems: Formulation Design and Applications

Self-emulsifying drug delivery systems (SEDDS) represent a paradigm shift in topical drug delivery, overcoming the critical challenges like stability of drug, poor drug penetration and suboptimal patient compliance. This review consolidates the current knowledge on use of topical SEDDS and furnishes an account of literature instances on it, while emphasizing on the key formulation aspects of SEDDS. It discusses components, classifications, and mechanisms of self-emulsification in SEDDS, along with role of the pseudo-ternary phase diagrams in optimization of formulation. The review explores different types of SEDDS like supersaturated (st-SNEDDS), and solid (s-SNEDDS), highlighting their advantages over the traditional formulations and associated challenges. Various databases, utilizing search engines like Google Scholar, PubMed, and Science Direct were used to search and collect relevant literature. Certainly, the use of SEDDS for topical delivery is quite promising, yet it is at evolving stage. The formulation strategies for the topical SEDDS are akin to oral SEDDS, however are not very well researched. In this regard, more studies need to be carried out for lucid comprehension of the mechanism of their absorption and strategies should be developed to counteract the irritation potential owing to use of surfactants. With a limited existing literature on the topical SEDDS, this area presents a substantial opportunity for exploration and innovation, paving way for more patient-friendly and effective topical formulations.