Development of Dispersible Self-microemulsifying Tablet of Atorvastatin

Aim: The aim of this study was to develop dispersible self-microemulsifying (SMEDDS) tablet of atorvastatin for promoting its solubility and thus its oral bioavailability. Materials and Methods: The liquid SMEDDS were prepared by water titration method using oil, surfactant and co-surfactant and converted into solid- SMEDDS (S-SMEDDS) by adsorption on solid carriers (Neusilin US2). The S-SMEDDS were blended with sodium starch glycolate (disintegrant) and tablet excipients and compressed into tablets that were dispersible and self-microemulsifying in nature. All these formulations were assessed for various physicochemical parameters viz. weight variation, hardness, friability, disintegration test. In vitro studies of pure drug, SMEDDS, S-SMEDDS and dispersible SME-tablets were carried out. Results: Pure drug released only 29.84 ± 0.16% upto 60 minutes and all the SMEDDS formulations (i.e. SMEDDS. S-SMEDDS and dispersible SME-tablets) released 100% of drug in comparatively lesser time. Formulations containing atorvastatin, 30% oleic acid, 65% tween 80 and 5% co-surfactant came out to show the best results in in vitro studies. But, FB1 (tablet) was considered to be the best since it released 100% drug in 35 min and also has advantages over SMEDDS and S-SMEDDS in terms of stability and patient compliance. Conclusion: The study revealed the potential use of dispersible SMEDDS tablet for the oral delivery of hydrophobic drugs, such as atorvastatin. Key words: Atorvastatin, Bioavailability, Phase diagram, SMEDDS.