Fatmanur TUĞCU-DEMİRÖZ*, Füsun ACARTÜRK*,?

*Gazi University, Faculty of Pharmacy, Department of Pharmaceutical Technology, 06330 Etiler, Ankara, TURKEY.
°Corresponding author

Summary:
Recently, colon-specific delivery systems have gained importance for the treatment of colon diseases and peroral administration of peptides\proteins. Oral administration of drugs in conventional pharmaceutical form is the most convenient and effective route and is preferred over parenteral medication. However, not all drugs can be administered orally, possibly because of their sensitivity to gastric acid and their vulnerability to gastrointestinal enzymes. The site-specific delivery of drugs to the target receptor sites has the potential to reduce side effects and to increase pharmaceutical response. One of the areas to target drugs orally for systemic drug delivery is the colon. Using different approaches, several potential colon-specific delivery systems have been developed. Among these, the most promising are prodrugs, coating with pH-sensitive polymers, matrix preparation and\or coating of drugs with colonic bacterial degradable polymers. The aim of this review was to provide a general overview to colon functions and physiology, drug absorption characteristics and of the technologies available for colon–specific drug delivery systems.