EVALUATION OF COMPATIBILITY OF TABLET EXCIPIENTS WITH ALBENDAZOLE ANDCLOSANTEL USING DSC AND HPLC

The compatibility between albendazole and closantel, with commonly use d tablet excipients, was assessed by studying drug-excipient mixtures mixed in 1:1 ratio and 1:1 ratios granulated with water and dried at 5 0 degrees C for 1 hr with a differential scanning calorimeter (DSC) an d high-performance liquid chromatograph (HPLC). Results showed that th ere were interactions between closantel and/or albendazole and some ta blet excipients. For example, magnesium stearate reacted with both dru gs and the interaction was observed by DSC and HPLC. Exposure of mixtu res, and even the drugs, to heat and moisture resulted in deteriorated compatibility as seen by both DSC and HPLC, but especially HPLC. Over all poor correlation between DSC and HPLC results was observed.