Formulation and Evaluation of Diclofenac Potassium Matrix Tablets

The objective of the study was to develop HPMC matrix tablets for oral controlled/ sustained release of water soluble Diclofenac Potassium. Sustained release matrix tablets containing 100 mg of Diclofenac Potassium were developed using different drug polymer ratio of HPMC. Tablets were prepared by direct compression. Compressed tablets were evaluated for uniformity of weight, content of active ingredient, friability, hardness, thickness and in–vitro dissolution study. All tablets but one exhibited gradual and near completion sustained release for Diclofenac Potassium and 98.72 % released at the of 12 hours. The results of dissolution studies indicating that formulation D5 (drug to polymer 1:1.40) the most successful of the study, exhibited drug release pattern very close to theoretical release profile. A decrease in release kinetic of the drug was observed on increasing polymer ratio. Applying the exponential equation, all the tablets (except D5) showed diffusion dominated drug release. The mechanism of drug release from D5 was diffusion coupled with erosion.