Sterility and Stability of Diluted Meloxicam in Compounded Multi-dose Vial after 365 Days

Meloxicam is a common analgesic for rodents. Because meloxicam is only formulated commercially for companion animals, it requires dilution to achieve doses appropriate for small, laboratory species. Compounded multidose vial (cMDV) are often created to dilute and store a diluted drug. However, chronic cMDV use runs the risk of contamination and becoming a potential source of nosocomial infection. In this study, we created 15 cMDV by diluting meloxicam with sterile water (dilution, 1:10). cMDV were punctured once daily for 30 d. To determine the sterility of the diluted meloxicam, we assessed 8 cMDV for bacterial growth on days 0, 10, 20, 30, and 365 and tested them for endotoxin on days 0, 30, and 365. In addition, the stability of the remaining 7 cMDV was assessed on days 0, 10, 20, 30, and 365, by using liquid chromatography-diode assays. No bacterial growth or endotoxin was detected at any time point, and the drug concentrations remained stable over 365 d. Given the results this study, we believe that cMDV of diluted meloxicam can remain sterile and stable for 365 d.