Preparation and In-vitro Evaluation of Sustained Release Phenytoin Sodium Matrix Tablets Prepared by Co-Evaporation Method Using Different Polymers

Sustained-release capsules of Phenytoin sodium were developed and evaluated. The Co-evaporation method was employed for the preparation of granules, hydroxy propyl methyl cellulose (HPMC), carboxymethyl cellulose (CMC) and polyvinylpyrrolidon-K90 (PVP-K90), were used as release sustaining materials. Formulations were designed using drug to polymers ratio 1:1, 1:1.5, 1:2 with the aim to develop twice daily sustained release capsules. Physical characterization of granules was evaluated. USP dissolution apparatus I was used for the In-vitro drug release study of the capsules. Drug release data was evaluated using various models like Zero-order, First-order, Higuchi model, Korsmeyer model and Hixson-Crowell model. The resulting capsules prepared with all the polymers were failed to fulfill the official criteria for dissolution required for a sustained dosage i.e. HPMC group of formulation with drug to polymer ratio 1:2 was able to controlled the release of the drug up to 8 hours, the CMC group with this ratio prolonged the release up to 6 hours and PVP group with the same ratio was able to sustained the release of the drug up to 4 hours.