THE ROLE OF PERCUTANEOUS PENETRATION ENHANCERS

It is clear that scientists are now only beginning to comprehend the c omplexity of transdermal drug delivery, Elucidation of the biochemical composition and functioning of the intrinsic diffusional barrier of t he stratum corneum has prompted investigation of chemical and physical means of enhancing the percutaneous penetration of poorly absorbed dr ugs. Chemical enhancers that aid absorption of co-administered moietie s are currently believed to improve solubility within the stratum corn eum or increase lipid fluidity of the intracellular bilayers, Alternat ively, the use of ionto- or phonophoresis may facilitate the absorptio n of some drug molecules by physical alteration of the barrier. The ro le of penetration enhancer inclusion in topical formulations has been well documented and will undoubtedly, in the future. permit the delive ry of broader classes of drugs through the stratum corneum.