zero order drug release

To develop and evaluate Push Pull Osmotic tablets of ketorolac Tromethamine (KT). Core tablets of KT were formulated by wet granulation method using polymers (HPMC K4M, K15M) , coated with semipermeable membrane (cellulose acetate), plasticizer (PEG 400) , pore former (D- sorbitol) and osmogen (sodium chloride). Compatibility studies were carried out using Differential Scanning Calorimetry(DSC), no incompatibility between the drug and polymers observed. The Physical properties of tablets were evaluated for thickness, hardness, friability, drug content, effect of osmotic agent, percentage of pore former, pH, agitational intensity, weight gain, osmotic pressure and in vitro drug release for 12 hours. Release studies best fitted to zero order pattern, indicating drug release was non-Fickian, independent of pH and agitational intensity. The system is simple, cost effective and alternative to conventional osmotic pump since sophisticated laser drilling technique is not required.