Chemical and Microbiological Stability of Extemporaneous Cardiovascular Suspensions Compounded in Dual Suspending...

Extemporaneous compounding plays a critical role in providing individualized pharmacotherapy for pediatric patients who require cardiovascular medications not available in commercially manufactured liquid formulations. This study evaluated the chemical, physical, and microbiological stability of clopidogrel, hydrochlorothiazide, nifedipine, propranolol, and spironolactone oral suspensions prepared in Flavor Sweet™ SF/Flavor Plus™ (1:1) (also marketed in Europe as Syra Sweet SF/Syra Plus), a widely used vehicle in pharmacy compounding. All formulations were prepared using a standardized protocol and stored at room temperature and refrigerated conditions for up to 90 days. Stability-indicating UHPLC methods were validated and applied to quantify drug content and monitor pH and physical characteristics throughout the study. Antimicrobial Effectiveness Testing was performed in accordance with USP <51>. Hydrochlorothiazide, nifedipine, propranolol, and spironolactone retained 90-110% of labeled content for at least 90 days under both storage conditions, while clopidogrel showed temperature-dependent degradation and met stability criteria for up to 90 days only under refrigeration. All formulations maintained consistent pH values and exhibited no visual changes. Microbiological evaluation confirmed effective preservative performance across all samples, with no microbial proliferation and full compliance with USP <51> acceptance criteria.