Determination of compatibility of fosaprepitant dimeglumine and magnesium sulfate injections by high-performance liquid chromatography

Fosaprepitant dimeglumine relieves nausea and vomiting caused by highly emetogenic chemotherapy agents such as high-dose cisplatin. Magnesium has renoprotective effects against cisplatin-induced damage. Thus, both drugs are sometimes used concomitantly, but administering them together intravenously may cause occlusion of the in-line filter. We aimed to clarify the extent to which the delivery of intravenous fosaprepitant dimeglumine is reduced by magnesium sulfate. Fosaprepitant dimeglumine was combined with magnesium sulfate and then filtered. Two ratios and concentrations of magnesium sulfate were tested (1:1 and 7:3 corresponding to 1.5 mg/mL fosaprepitant dimeglumine solution to 3.85% and 0.99% magnesium sulfate solution (v/v), respectively). The concentration of fosaprepitant dimeglumine in the filtrates was measured via high-performance liquid chromatography to determine the rate of decline in fosaprepitant dimeglumine. These experiments were performed in triplicate. When the ratio of fosaprepitant dimeglumine to magnesium sulfate was 1:1, the maximum rate of decline for fosaprepitant dimeglumine was 38.67%. At a ratio of 7:3, the maximum rate of decline was 7.62%. Fosaprepitant dimeglumine likely reacted with magnesium sulfate, which might inhibit the efficacy of fosaprepitant. To prevent this, we recommend flushing the in-line filter with 50 mL of normal saline before and after the administration of fosaprepitant dimeglumine.

fosaprepitant dimeglumine

magnesium sulfate

drug compounding

high-performance liquid chromatography

infrared spectroscopy