Colon Targeted Drug Delivery: Different Approaches

Oral colon-targeted drug delivery systems have recently gained importance for delivering a variety of therapeutic agents for both local and systemic administration-local treatment of a variety of colonic diseases as well as systemic absorption of proteins and peptides. Targeting of drugs to specific sites of action provides several advantages over non-targeting of drugs. The colon, as a site for drug delivery, is also beneficial for the treatment of diseases sensitive to circadian rhythms and delivery of poorly absorbable drugs. The successful targeted delivery of drugs to the colon via the gastrointestinal tract requires the protection of a drug from degradation and release in the stomach and small intestine and then ensures abrupt or controlled release in the proximal colon. This review will cover both past and present approaches for achieving colon specific drug delivery.