COLON SPECIFIC DELIVERY SYSTEM: THE LOCAL DRUG TARGETING

Abstract

Oral administration of different dosage forms is most commonly used method due to greater flexibility in design of dosage form and high patient acceptance, but gastrointestinal tract presents several formidable barriers to drug delivery. The colon is a site where both local and systemic delivery of drugs takes place. Local delivery could, for example, allow topical treatment of inflammatory bowel diseases. In colon specific drug delivery system, colon has a large amount of lymphoma tissue (facilitates direct absorption into blood), negligible brush border membrane activity, and much less pancreatic enzyme activity as compared with small intestine. Colon specific drug delivery has gained potential for delivery of proteins and therapeutic peptides. Different approaches are designed based on prodrug formulation, pH sensitivity, time dependency, microbial degradation and osmotic pressure etc. But these systems have limited success. Newly developed CDDS are developed which includes pressure controlled colonic delivery capsules, osmotic controlled drug delivery systems which are unique in terms of achieving in vivo site specificity and feasibility of manufacturing process.