Dissolution properties and anticonvulsant activity of phenytoin-polyethylene glycol 6000 and -polyvinylpyrrolidone K-30 solid dispersions

Solid dispersions of phenytoin in polyethylene glycol 6000 and polyvinylpyr rolidone K-30 with different drug-to-carrier ratios were prepared by the so lvent method with the aim of increasing dissolution rate and bioavailabilit y of the drug. These new formulations were characterized in the solid state by FT-IR spectroscopy, X-ray powder diffraction, and differential scanning calorimetry. Drug solubility and dissolution rate are improved by these fo rmulations, particularly with SDPEG 1/20 and SDPVP 1/20 systems. Storage wa s found to influence the stability of the solid dispersions. By maximal ele ctroshock test, it was found that the intraperitoneal administration in mic e of the SDPEG 1/20 and SDPVP 1/20 systems exhibited anticonvulsant activit y similar to diphenylhydantoin sodium salt. (C) 2001 Elsevier Science BN. A ll rights reserved.