For each drug — ibuprofen, naproxen, nimesulide, and paracetamol — calibration curves and release profiles were determined. Experiments were carried out in phosphate buffer (pH 7.4) using UV-Vis spectrophotometry, with concentrations calculated from absorbance measurements. Results indicate two distinct release behaviors: Ibuprofen and nimesulide: gradual release, reaching maximum concentration after 24 hours Naproxen and paracetamol: rapid release, reaching full release within 30 minutes