Compatibility of Norepinephrine Bitartrate with Levofloxacin and Moxifloxacin During Simulated Y-site Administration.

The purpose of this study was to determine the physical compatibility and chemical stability of norepinephrine bitartrate with selected fluoroquinolones during simulated intravenous Y-site administration. Simulation of Y-compatibility of intravenous fluids can be experimentally demonstrated by mixing equal volumes of two drugs of interest. Hence, we prepared 1:1 mixture of norepinephrine bitartrate and levofloxacin or moxifloxacin by mixing 64 .g/mL of norepinephrine bitartrate individually with clinically relevant concentrations of levofloxacin (5 mg/mL) and moxifloxacin (1.6 mg/mL). The physical stability of these mixtures was assessed via measurement of change in turbidity, and visual inspection for color change, haziness, and precipitate formation. The chemical stability of these mixtures was assessed via high-performance liquid chromatography by evaluating the change in concentration for norepinephrine bitartrate and individual fluoroquinolones, from 0 to 4 hours after mixing. The visual evaluation and turbidity measurements revealed that norepinephrine bitartrate is compatible with individual fluoroquinolones. No color change, haziness, or precipitate formation was observed at 0 and 4 hours when the drugs were mixed at equal volume. The change in turbidity for the mixture as compared to the individual drugs was very minimal (0.001 to 0.004 nephelometric turbidity unit). No significant change in drug concentrations was observed during the 4-hour period for norepinephrine bitartrate and the individual fluoroquinolones following high-performance liquid chromatography analysis of the norepinephrine bitartrate/levofloxacin and norepinephrine bitartrate/moxifloxacin mixtures, which further confirms the stability of this mixture. Our data indicates that norepinephrine bitartrate is compatible with levofloxacin and moxifloxacin, and can be used for intravenous Y-site administration with either of these fluoroquinolone antibiotics.