Stability of Dexamethasone Sodium Phosphate in Intravenous Admixtures

Abstract

Objective: Diluted IV solutions of dexamethasone sodium phosphate (DSP) are often used in prophylactic treatment of chemotherapy-induced nausea and vomiting. However, there is limited data to support the selection of diluents, storage conditions, and beyond-use dates. This study was designed to investigate these parameters. Methods: DSP injection 100 mg/10 mL vials were used to prepare the IV admixtures in two diluents and at two drug concentrations (0.08 or 0.4 mg/mL). The admixtures were packaged in PVC bags and stored at room temperature or under refrigeration for up to 14 days. On day-0, 1, 3, 7, and 14, each IV bag was inspected visually, and a sample was withdrawn for pH and HPLC analysis. Results: The freshly prepared admixtures of DSP appeared clear, colorless, and free of particulates. The initial pH values were 6.4-6.8 and 7.0-7.8 for bags in 0.9% sodium chloride and 5% dextrose, respectively. The initial DSP concentrations of all samples were within 96 – 100% of the expected values. Over the 14 days of storage at room temperature or refrigeration, no significant change was observed for the visual appearance of any IV bags. The pH of all samples remained within one pH unit from the initial values. The HPLC results confirmed that all samples retained 94 – 100% of original drug concentrations. Implications: IV admixtures of 0.08 - 0.4 mg/mL DSP are compatible with 0.9% sodium chloride and 5% dextrose in PVC bags. These admixtures are also chemically and physically stable for up to 14 days when stored at room temperature or under refrigeration