A Description on Study of Intestinal Barrier, Drug Permeability and Permeation Enhancers

Penetration enhancers are present in a large number of transdermal, dermatological, and cosmetic products to aid dermal absorption of curatives and aesthetics. Delivery of hydrophilic drug by per oral route has always fascinated the researchers. Hydrophilic drugs show low bioavailability through oral administration because of their poor intestinal permeation & absorption. In the last few years there has been great interest focused on search of different intestinal permeation enhancers for the oral delivery of BCS class III drugs, small polar molecules, vaccines, hormones, peptides and proteins, which are well suitable for the delivery of the above products to give enhanced bioavailability by increasing intestinal permeability. This review targets to discuss functioning, anatomy and physiology of the intestinal barrier, drug absorption from intestinal tract, mechanism of intestinal drug permeability, detail information about intestinal permeation enhancers and its mechanism of action, invitro methods for studying drug permeability, and importantly the advantages and applications of newer permeation enhancers.