New molecular entities had presented a challenge to the scientific community worldwide with bioavailability issues and compromised potential therapeutic efficacy. Designing and synthesizing new chemical derivatives of these molecules is a highly time and cost consuming process. Thus, rationale for planning novel strategies to address the issue is acceptable. In this context, development of targeted drug delivery system for highly variable and narrow therapeutic indexed drugs provides a rationale approach, which could subsequently reduce the dose, its variability and cost. One such approach is colon targeted drug delivery system (CDDS) that means delivery of drug to the lower large intestine (colon in humans) preventing the release of drug in upper gastrointestinal tract (GIT). Colon targeted drug delivery systems holds promise for direct and more effective delivery of therapeutic agents to the colon for patients being treated for illnesses such as irritable bowel syndrome (IBS) or irritable bowel disease (IBD) in colonic cancer,ulcerative colitis, Crohn s disease, diverticulitis, haemorrhoids etc.