Stability of capsules containing omeprazole in enteric coated pellets

The aim of the present study was to comparatively evaluate the stability of capsules containing 20 mg of Omeprazole, in enteric coated pellets, from seven pharmaceutical laboratories on Argentine market. The stability test was performed under the conditions indicated by the ICH: 40 degrees C, 75% HR, with and without light, during a six month period. The remaining content of Omeprazole, total percentage of impurities and percentage of released active principle in vitro, were determined by HPLC. The organoleptic characteristics of the pellets were visually examined. The results obtained at six months indicate that, from the seven products studied, four were found to have a content of Omeprazole higher than 90% of the labeled amount, in both lighting conditions tested, and also comply with the USP23 specifications with respect to the release in vitro. We conclude that the progressive darkening of the pellets indicates, qualitatively, the level of degradation of the product and that the stability of Omeprazole depends on the correct formulation and the primary container.