A Novel SMEDDS Approach To Enhance Solubility And Dissolution Of Poorly Water-Soluble Norethisterone

Abstract

The objective of this research was to formulate a self-microemulsifying drug delivery system (SMEDDS) to improve the dissolution profile of norethisterone. To identify appropriate excipients, solubility evaluations were carried out in different oils, surfactants, and co-surfactants. A ternary phase diagram was used to optimize the combination and concentration of components. The final formulation consisted of 5 mg norethisterone, 14.48% w/w Capmul PG8, 56.84% w/w Cremophor EL, and 28.68% w/w propylene glycol. It exhibited favorable characteristics, including a pH of 6.43 ± 0.05, drug content of 98.32 ± 0.95%, emulsification within 30 seconds, and a cloud point of 58.41 ± 0.45°C. In vitro dissolution studies confirmed a significantly improved drug release (99–100%) compared to pure norethisterone. The results indicate that SMEDDS can be an effective approach to improve the dissolution and potentially the bioavailability of drugs with low water solubility, such as norethisterone.