Lipids in oral controlled release drug delivery

Lipids can perform many useful functions that modify or otherwise enhance drug absorption or disposition. They may influence release/absorption-controlling processes, such as gastro retention and muco-adhesion. They can facilitate lymphatic transport of lipophilic drugs, and make them less susceptible to first pass effects by avoiding or reducing the hepatic portal route. Understanding lipid digestion and structure formation in vivo is key to exploiting possibilities for their use in controlling absorption or disposition. In particular, liquid crystalline structures are being increasingly investigated for their roles in the aforementioned processes. Such phenomena and possibilities are discussed in this chapter.