Development and Optimization of a Lipid-Based Self-Nanoemulsifying Drug Delivery System (Snedds) for Enhancing the Lymphatic Absorption and Bioavailability of Silymarin.

Background: Silymarin, a potent hepatoprotective agent, suffers from poor aqueous solubility (BCS Class II/IV) and extensive first-pass metabolism, leading to low oral bioavailability (<5%). Objective: To formulate a lipid-based SNEDDS to facilitate lymphatic transport and bypass hepatic metabolism. Methods: Solubility studies in various oils, surfactants, and co-surfactants. Pseudo-ternary phase diagrams were constructed. Optimization was done using a Box-Behnken design. Results: The optimized formula showed a globule size of <100 nm and significantly higher drug release compared to pure Silymarin. Conclusion: The SNEDDS formulation is a promising strategy for improving the therapeutic efficacy of Silymarin.