Delayed release drug delivery systems are a major advance towards solving problems concerning the stability and solubility of drug in gastrointestinal tract and thereby release the drug in the small intestine. Naproxen is a non-selective Cyclooxygenase (COX) inhibitor, which is insoluble in acidic environment and cause gastric distress or irritation. In order to prevent the gastric irritation, Naproxen is designed to formulate as Enteric coated tablet which is more soluble in pH 6.8 at small intestine.

Keywords: Naproxen; Cyclo-oxygenase (COX) inhibitor; Delayed release drug delivery systems.