ABSTRACT

The purpose of this work was to develop extended release (ER) matrix tablets of gabapentin, an anticonvulsant drug. The tablets were prepared by direct compression method along with hydrophilic matrix materials like HPMC K4M, HPMC K 15M and HPMC K 100M. The blends were evaluated for bulk density, angle of repose and compressibility index. The tablets subjected to thickness, diameter, weight variation test, drug content, hardness, friability, and in vitro release studies in 0.1N HC1 solution for the initial 2h, followed by pH 6.8 phosphate buffer Solutions up to 12 hours. The drug release study revealed that matrix tablets containing HPMC K 15M and HPMC K 100M polymer exhibited more extended release than the tablets containing other polymers. Formulation F7 showed desired drug release up to 12 h. For the optimized formulation, kinetic modeling of in vitro dissolution profiles revealed the drug release mechanism ranges from diffusion controlled or Fickian transport to anomalous type or non-Fickian transport. Fitting the in vitro drug released data to Korsmeyer equation indicated that diffusion along with erosion could be the mechanism of drug release in optimized formulation F7.