A self-emulsifying drug delivery system (SEDDS) of a poorly water soluble drug, irbesartan
(IRB), was designed. The aim was to improve the solubility as well as dissolution rates of IRB. Solubility of
IRB in different vehicles were determined and a pseudoternary phase diagram was constructed as preliminary
studies to formulate SEDDS. From the pseudoternary plot it was observed that the microemulsion
existence area increased as the surfactant-cosurfactant ratio (Smix) increased and increasing the surfactant
ratio, loss of flowability was observed. Smix of 3:1 and 4:1 were selected for formulating SEDDS. After
formulation emulsification, dispersibility test and thermodynamic stability studies were performed.
From dissolution results, it was observed that increasing oil-surfactant ratio, the rate of dissolution of IRB
was decreased and the dissolution rate was increased with the increasing the Smix ratio. Dispersibilty test
showed that most of the formulations falls within the grade B. Least emulsification time was found for F-1
and all the formulations were found to be thermodynamically stable with slightly deviations.