A Review on SEDDS for Ulcerative Colitis

Ulcerative colitis (UC) is a chronic idiopathic inflammatory bowel disease (IBD) characterised by continuous mucosal inflammation extending proximally from the rectum, affecting approximately 5 million people worldwide as of 2023, with rising incidence in developing regions including India. First described by Samuel Wilks in 1859, UC typically presents in the second or third decade of life with cramping abdominal pain and bloody diarrhoea, following a relapsing–remitting course. Its multifactorial pathogenesis involves genetic susceptibility (NOD2/CARD15, IL23R, IL10 variants), immune dysregulation through NF-κB, JAK/STAT, NLRP3, and IL-23/IL-17 signalling pathways, gut microbiome dysbiosis, and epithelial barrier dysfunction. A major pharmaceutical challenge is that over 40% of anti-inflammatory drug candidates exhibit poor aqueous solubility (BCS Class II/IV), severely limiting oral bioavailability. Self-Emulsifying Drug Delivery Systems (SEDDS) — isotropic mixtures of oils, surfactants, and co-solvents — overcome this by spontaneously forming fine oil-in-water emulsions in gastrointestinal fluids; advanced variants SMEDDS (100–250 nm) and SNEDDS (<100 nm) offer nanoscale droplets with superior absorption and thermodynamic stability. This review integrates current knowledge of UC pathogenesis with the therapeutic potential of SEDDS-based colon-targeted delivery as a strategy to improve drug bioavailability and clinical outcomes.