PHYSICAL AND CHEMICAL COMPATIBILITY OF INTRAVENOUS CIPROFLOXACIN WITHOTHER DRUGS

OBJECTIVE: To determine the physical and chemical compatibilities of c iprofloxacin lactate infusion with other commonly used intravenously a dministered drugs. DESIGN: Ciprofloxacin lactate injection in a commer cially available concentration of 2 mg/mL was mixed with 15 intravenou s drugs during simulated Y-site injection. Ciprofloxacin was mixed wit h usually employed concentrations of other drugs in a 1:1 ratio and ex amined physically by visual inspection and chemically by HPLC analysis . Adsorption of ciprofloxacin to intravenous administration sets with or without inline filters was also studied. SETTING: The study was car ried out at ambient temperature (25-degrees-C) under fluorescent light ing except for vitamin B complex, which was protected from light. All samples were prepared in a laminar airflow hood. MAIN OUTCOME MEASURES : Physical incompatibility was determined by visual inspection against a black-and-white background, and chemical incompatibility was measur ed by a stability-indicating HPLC assay for ciprofloxacin. Concentrati ons determined at time zero (before mixing) were defined as 100 percen t. Values estimated for each sample at subsequent time points were cal culated as percentages of the initial concentration. Recovery below 90 percent of the initial concentration is defined as significant loss. RESULTS: Of the 15 drugs studied, only heparin, furosemide, and teicop lanin were found to be incompatible with ciprofloxacin. Adsorption of ciprofloxacin to administration sets with and without inline filters w as minimal. Metronidazole was also found to decrease to 90 percent of its initial concentration immediately upon mixing. CONCLUSIONS: Ciprof loxacin ready-to-infuse solution is compatible with most of the drugs studied except heparin, furosemide, teicoplanin, and, perhaps, metroni dazole. Because only the stability and potency of ciprofloxacin were s tudied, further testing is needed to confirm if any chemical deteriora tion of the other drugs occurred when combined with ciprofloxacin.