Compatibility and Physical Properties of Dexamethasone-Ondansetron Intravenous Admixture

Purpose: This work aimed at evaluating the impact of different concentrations and final volumes on the compatibility and physical properties of dexamethasone-ondansetron intravenous (IV) admixture. Methods: The IV admixture of dexamethasone-ondansetron was prepared at different concentrations using normal saline solution as solvent. The final volume of the IV admixture was prepared at 50 and 100 ml. Turbidity was measured as an indicator of physical compatibility of the IV admixture of dexamethasone-ondansetron using UV-visible spectrophotometer and the pH of the IV admixture was measured on day 0, 7,14, and, 21 as an index of chemical stability. Also, the particle size and potential molecular interactions of the admixtures were determined using particle size analyzer and Fourier Transform infrared spectrometry analysis, respectively. Additionally, the effect of preservatives on the IV admixture was also evaluated. Results: Precipitation was observed for mixtures with amounts of dexamethasone and ondansetron exceeding 8 and 16 mg, respectively, in a final volume of 50 ml. For all mixtures with final volume of 100 ml, clear solutions void of any precipitates were observed. The pH of the solution had no effect on the precipitation of the dexamethasone-ondansetron during storage up to 21 days. Analyses of the precipitate formed revealed the presence of molecular interactions between dexamethasone and ondansetron. The benzyl alcohol used as a preservative affected the compatibility of the IV admixture compatibility. Conclusion: Thus, for the preparation of clear, physically compatible normal saline solutions of dexamethasone-ondansetron IV admixture, the maximum amounts of the respective drugs should not exceed 8 and 16 mg in total volume of 50 ml or 20 and 16 mg in a final volume of 100 ml.