Main Article Content
Abstract
Colon-targeted drug delivery systems (CTDDS) have gained significant importance due to their ability to deliver drugs selectively to the colon, thereby improving therapeutic efficacy while minimizing systemic side effects. Conventional oral drug delivery often results in premature drug release and degradation in the upper gastrointestinal tract, making targeted colonic therapy challenging. This review provides a comprehensive overview of the progress, strategies, challenges, and future prospects of colon-specific drug delivery systems. Various physiological factors influencing colonic drug delivery, including pH variation, transit time, colonic microflora, and enzymatic activity, are discussed in detail. The article highlights primary approaches such as pH-dependent systems, time-controlled release systems, and microbially triggered drug delivery, along with advanced techniques like prodrug strategies, polysaccharide-based systems, pressure-controlled devices, osmotic systems, nanoparticle based delivery, microbiota-responsive systems, and 3D-printed drug delivery platforms. Evaluation methods, marketed formulations, advantages, limitations, and recent technological advancements are also reviewed. Despite remarkable progress, challenges such as formulation variability, site-specificity issues, scale-up difficulties, and physiological variability remain. Future perspectives emphasize the integration of advanced predictive tools, novel polymers, nanotechnology, and manufacturing techniques like hot-melt extrusion and 3D printing. Overall, CTDDS represents a promising and evolving approach for effective management of colonic diseases and systemic drug delivery.