In the present investigation, an attempt has been made to increase therapeutic efficacy, reduce frequency of administration and improve patient compliance by developing sustained release matrix tablets of theophylline. Sustained release matrix tablets of theophylline were developed by using drug and different concentrations of polymer such as 10, 20, 30, 40 and 50%. Hydroxypropylmethylcellulose (HPMC) was used as a matrix material and microcrystalline cellulose as diluent. All the lubricated formulations were compressed using 10 mm flat faced punches. Compressed tablets were evaluated for uniformity of weight, drug content, friability, hardness, thickness, in vitro dissolution and swelling index. All the formulations were found to be within pharmacopoeial standards. Among the different formulations, F1 showed sustained release of drug for 12 h with 84.23% release. The effect of release modifier (PEG 6000) on in vitro drug release was also studied. Thus, HPMC can be used as an effective matrix former, to extend the release of theophylline

The objective of the present investigation was to develop and evaluate sustained release matrix tablets of prochlorperazine maleate employing different types and levels of hydrophilic matrix agents namely hydroxyl propyl methyl cellulose (HPMC), carbopol and combination of these polymers by wet granulation technique. Prior to compression process, the prepared granules were evaluated for its flow and compression characteristics. The in vitro dissolution of the newly formulated sustained release tablets were compared with standard formulation. The excipients used in this study did not alter the physicochemical properties of the drug, as indicated by the thermal analysis using differential scanning calorimetry technique. The flow and compression characteristics of the prepared granules significantly improved by virtue of granulation process. Also, the prepared matrix tablets showed good mechanical properties in terms of hardness and friability. HPMC based tablet formulations alone showed high release retarding efficiency as compared to carbopol, carbopol and HPMC combinations. The studies indicated that the drug release can be modulated by varying concentrations of polymers. Mathematical analysis of the release kinetics indicated the nature of the drug release from the matrix tablets followed quasi-fickian obeying first order kinetics.