Novel Approaches in Colon Targeted Drug Delivery Systems

Although oral delivery has become a widely accepted route of administration of therapeutic drugs, the gastrointestinal tract presents several formidable barriers to drug delivery. Colonic drug delivery has gained valued attention not just for the targeted delivery and effective therapy of local diseases associated with the colon but also for its potential for the delivery of proteins and therapeutic peptides. A successful and precise colon drug delivery system requires a drug to be protected from upper gastrointestinal tract and an abrupt release into the optimum site of the colon i.e. proximal colon. This review is an attempt to revise the basic concepts and aspects of colon targeted drug delivery systems and also encompasses an overview of diseases of the colon viz. inflammatory bowel disease (IBD), Ulcerative colitis, Crohn’s disease and colon cancer. Among the different approaches available to achieve targeted drug release to the colon, the use of especially biodegradable polymers holds great promise. The various primary and novel approaches for effective targeting in the colon have also been discussed briefly.