RECENT ADVANCES IN COLON TARGETED DRUG DELIVERY SYSTEM: AN UPDATE

ABSTRACT Colonic drug delivery has gained interest for the delivery of drug for the treatment of local diseases which allows for treatment of inflammatory bowel disease associated with colon and systemic delivery of therapeutic peptides and proteins and its side effects could be reduced. The drug directly delivered to colon then its treatment is more effective. The colon is often a prospective site for the systemic absorption of a handful of drugs for the treatment of non-colonic conditions. Improved drug delivery systems are essential for drugs currently in use to treat localized diseases of the colon. Drugs like proteins and peptides that are identified to degrade in the extreme stomach pH scale, if delivered to the colon intact, can be systemically absorbed by colonic mucosa. In order to attain effective therapeutic results, it is imperative that the designed delivery system specifically targets the drugs into the colon. The various strategies for targeting administered drugs to the colon include coating with pH-sensitive polymers, formulation of timed released systems, bio adhesive systems and osmotic controlled drug delivery systems. The advantages of targeting drugs precisely to the diseased colon are reduced frequency of systemic side effects, lower dose and supply of the drug to the bio-phase only when it is required and maintenance of the drug in its intact form as close as possible to the target site. This study is based on anatomy and physiology of the colon advantages, limitations, and their approaches for targeted delivery at a specific site of the colon. KEYWORDS: Colon drug delivery, novel approaches, inflammatory Bowel disease, polymers