PREPARATION AND EVALUATION OF SUSTAINED RELEASE MATRIX TABLETS OF NITROFURANTOIN

Aim of the present work was to prepare and evaluate sustained release (SR) matrix tablets of Nitrofurantoin (NF), for the treatment and prevention of urinary tract infections and better patient compliance. The SR-NF matrix tablets were prepared by direct compression method using different ratios of ethyl cellulose, HPMC K4M, sodium alginate and carbopol. Total three sets, each set consisting of three formulations, overall nine formulations viz., F-1 to F-9 were prepared. The prepared SR-NF matrix tablets were evaluated for precompression, postcompression parameters, drug content and in vitro drug release. All formulations (F1 – F9) which shows burst release during initial stages of dissolution. The release of nitrofurantoin from the matrix tablets was controlled up to 12 hr. The cumulative percentage of drug release was decreased with increase in polymer concentration. Among all formulations HPMC K4M released maximum amount of drug as it’s a hydrophilic matrix polymer that hydrates, forms a gel layer, and controls drug release by diffusion and erosion. A burst release of 20–30% may occur because drug particles are present on or near the tablet surface. The drug release was independent of its concentration and the mechanism of drug release followed non-fickian diffusion. It is concluded that sustain release matrix tablets of Nitrofurantoin gives all satisfactory results for formulation F1-F9. The increase in polymer ratio was found to influence the release of drug from the formulations.