Drug release from eudragit e-coated mini tablets for colon targeting: in vitro study

摘要

Colon-specific drug delivery from solid oral dosage forms may be achieved with enzyme-controlled, time-controlled, and pH-controlled drug release mechanisms, respectively. Recently it has been shown that in severe ulcerative colitis the luminal contents of the colon show a very low pH of 2.3-4.7. A dosage form designed for drug release at this low pH should be able to deliver the drug selectively to the colon of patients with ulcerative colitis. Ou recently developed colonic dosage form consists of drug cores which are coated with the acid-soluble poly(methacrylate) Eudragit~circle R E to provide for drug release only under the acidic conditions of the inflamed colon. The objective of this study was to investigate the influence of hydrodynamic stress and additional coating layers on the drug release from Eudragit E-coated mini tablets.