Colon specific drug delivery via oral route faces several challenges. The drug must neither be absorbed from upper GIT nor be degraded in small intestine lumen. To serve the purpose desired dosage form prevents drug release in the upper GIT and deliver maximum drug content in the colon. Biodegradable polymer (carbohydrate) based drug delivery approach seems quite promising in delivering the drug to colon. Polysaccharides arriving from small intestine are the main source of nourishment for microflora in the colon. The ability of colon microflora to degrade, polysaccharides such as pectin, cross linked guar gum, chitosan forms the basis of formulation development for colon specific drug delivery. Cross linked guar gum has been successfully used as a drug carrier in matrix tablets for colonic drug delivery. Disturbance of GIT microflora is quite common during antibiotic therapy. Drug therapy for colon cancer, irritable bowel syndrome, ulcerative colitis and Crohn"s disease may be failed since antibiotic therapy is quite common during mentioned illnesses. The. present matrix tablet or granule or powder fornajjlation delivers major fraction of the drug from formulation specifically at colon. The matrix tablet comprise of at least a drug, spores -of lactobacillus and/or bifidobcterioum, and a naturally occurring gum (preferably guar gum, fenugreek gum, pectin, locust bean gum). The incorporation of spores of lactobacillus or /and bifidobacterium will ensure the delivery of the drug to the colon in certain cases where GIT microflora is disturbed. The developed oral formulation will find following applications: in the treatment of colon cancer, irritable bowel syndrome, ulcerative colitis and Crohn"s disease, protein and peptide delivery controlled and prolonged drug therapy. The said formulation selectively deliver the drug to colon henceforth the dose of incorporated drug reduced that consequently will lower the associated side effects.
