Formulation and Evaluation of Theophylline Controlled Release Matrix Tablets using Guar gum

Theophylline controlled release matrix tablets were prepared with guar gum in two ratios and with three different hardness of 5, 6 and 7 kg/cm. Theophylline controlled release granules were prepared and evaluated for the angle of repose, bulk density, tapped density, compressibility index and Hausners ratio. All the formulation showed good flow properties. The compressed tablets were evaluated for the hardness, uniformity of weight, friability, drug content and invitro dissolution studies. All the formulations showed compliance with pharmacopial standards. There was no interaction between drug, polymer and other excipients. It was confirmed by FTIR studies. Among all the formulations F-6 (i.e. polymer ratio 1:2 and hardness 7 kg/cm2) showed prolong release when compare to other formulations. The drug release kinetics showed zero order. The optimum formulation (F-6) was stable when it was stored at 40 + 20 C, 280 + 20 C and at 450 + 20 C for 6 months.