Role of chitosan in transdermal drug delivery

Transdermal drug-delivery systems (TDDS) are intended to deliver the target drug through the patient’s skin. Physicochemical, morphological, biophysical properties are the crucial factors that need to be considered for drug delivery through human skin. Using the TDDS mode drug can be administrated in a controlled manner and it allows continuous supply of those drugs also having shorter half-lives. This route of administration has increased patient compliance compared to the injectable form due to better possibility of self-administration and ease in termination of therapy, moreover, unlike the oral route it also avoids first-pass metabolism. Among the various challenges encountered in TDDS, the main challenge is low permeability of skin and various strategies have been reported for enhancing the transportation of drugs through the skin by overcoming the low permeable barrier. This chapter provides valuable information regarding use of chitosan in the TDDS. In the last two decades, various transdermal patches fabricated from different types of polysaccharides are explored, among which chitosan-based patches have shown growing interest mainly attributed due to its nontoxic nature, biocompatibility, nonskin irritancy, and its unique film-forming abilities. The chapter also focuses on the role of chitosan in the development of diverse kinds of TDDS such as hydrogel, microneedles, thin films, liposomes, electrospun hybrid nanofibers, emulsion, and some other miscellaneous formulation.