Stability of rifampin in SyrSpend SF

Rifampin is a bactericidal antibiotic drug of the rifamycin group. It is a semisynthetic drug produced from the bacterium Streptomyces mediterranei. Rifampin is commonly manufactured in capsule, tablet, and syrup dosage solutions containing alcohol or sorbitol. The objective of this study was to determine the stability of rifampin in SyrSpend SF. The studied samples were compounded into 25-mg/mL suspensions and stored in low-actinic bottles at room temperature and refrigerated conditions. Samples were assayed at each time point out to 60 days by a stability-indicating high-performance liquid chromatography method. The method was validated for its specificity through forced-degradation studies. The sample remained within 90% to 110% of the initial concentration throughout the course of the study. Based on data collected, the beyond-use date of the preparation is at least 60 days when refrigerated or stored at room temperature and protected from light.