LAUSR

This investigation was aimed to develop and evaluate lipid nanoemulsion-based gel of finasteride for topical administration, to increase drug availability into the skin for a long duration and to improve the in vivo potential of finasteride against alopecia. Nanoemulsion was prepared by a high-speed homogenization method using Vit E oil, cholesterol, and soya lecithin, characterized, and thickened using guar gum (nanoemulgel). Nanoemulgel was evaluated for pH, viscosity, drug release, skin permeability, and in vivo efficacy against alopecia. Size of the drug-loaded nanoemulsion droplets was observed to be 195.20 ± 9.43 nm with uniform size distribution (PDI; 0.25 ± 0.08) and negative zeta potential (− 7.61 ± 1.35 mV). The pH 5.37 ± 0.74 of the developed gel was found to be near to the skin pH. Gel showed slow release (94.77% in 24 h) and restricted permeation through the skin, i.e., 30.7% in 24 h. Macroscopic examination showed improved hair growth in the case of nanoemulgel. Hair diameter and length were observed to be increased significantly in the case of gel as compared with the testosterone treated group. The histological investigation supports the result of macroscopic examination where nanoemulgel restored the conditions (short length hair, necrotic cell appearance with miniaturized follicles) created by testosterone on the skin. Moreover, the developed formulation was observed to be safe and stable for at least 90 days. The results prove the clinical pertinence of this stable gel as it ensured longer stay over the skin, slower permeation and higher efficacy against alopecia.