Effect of Oil, Water, and Surfactant Mixture on the Physicochemical Properties and Transdermal Delivery of Finasteride-Loaded Microemulsions: Evaluation and Prediction Using Response Surface Methodology

The study investigated the use of microemulsions (MEs) as a topical delivery system for finasteride, a drug used to treat androgenetic alopecia, to avoid the systemic side effects associated with oral administration. The research focused on the effects of different oil, water, and surfactant mixtures on the physicochemical properties of finasteride-loaded MEs. The study found that a microemulsion system with a surfactant mixture ratio of 3:1 provided the largest microemulsion area and that finasteride did not alter the physicochemical properties of the MEs. In vitro skin permeation tests showed that formulations with higher water concentrations had greater permeation flux. The study concluded that response surface methodology could predict the relationship between ME composition and physicochemical properties, suggesting the potential for developing an optimal transdermal delivery formulation for finasteride. However, further investigation into other formulation properties, such as entrapment efficiency, skin retention, toxicity, and stability, was recommended.