FACTORS AFFECTING THE EFFICIENCY OF A SELF-EMULSIFYING ORAL DELIVERY SYSTEM

Dosage forms containing a self-emulsifying system have shown significa nt promise in improving the in vitro dissolution rate and oral absorpt ion of lipophilic drugs. In such a system, a surfactant, or a surfacta nt plus medium chain monoglyceride (co-emulsifier), is added to a lipo philic vehicle (oil) containing dissolved drug. In the present study, surfactants with different hydrophile-lipophile balance (HLB), fatty a cid glycerides (co-emulsifiers) with varying fatty acid (C-8-C-18) cha in length, and lipophilic vehicles (oils) containing different fatty a cid (C-8-C-18) compositions were evaluated for their effectiveness in producing self-emulsifying systems. This investigation showed that the HLB of the surfactant, as well as the fatty acid chain length of the monoglyceride have a significant effect on the performance of the self -emulsifying system; a surfactant with an HLB in the range of 10-15 an d a monoglyceride of medium chain fatty acid (C-8-C-10) were most effe ctive. Also, there ape certain critical concentrations of surfactant a nd monoglyceride necessary for preparing an optimum self-emulsifying o ral drug delivery system.