Kinetics of degradation of imidapril hydrochloride in finished dosage formulations.

This study investigates the impact of relative air humidity and temperature on the stability of imidapril hydrochloride (IMD) tablets. For this purpose the forced degradation test was used and the following environmental conditions were employed: RH = 76.4% and the temperature range of 313 - 333 K. For the determination of IMD content in the analyzed samples a reversed-phase high performance liquid chromatography (RP-HPLC) technique was used. Three series of tablets were prepared: whole-blistered tablets, whole-bare tablets and halved-bare tablets, in order to analyze the influence of different in-home storage habits on IMD tablets' quality. In the course of the study, the degradation of IMD was observed in each series of tablets. The kinetic mechanisms and the thermodynamic parameters of these reactions were established. It was evidenced that halved IMD tablets stored without immediate packaging retain their quality only for 12 days while tablets stored according to label recommendations are stable for 513 days.