Endothelial cell compatibility of trovafloxacin and levofloxacin for intravenous use

Levofloxacin and trovafloxacin have excellent activity against a variety of Gram-positive and Gram-negative organisms resistant to the established age nts. One local side-effect closely related to the use of parenteral fluoroq uinolones is phlebitis. To evaluate the effect of trovafloxacin and levoflo xacin on endothelial cell viability, intracellular levels of adenosine 5'-t riphosphate (ATP), adenosine 5'-diphosphate (ADP), guanosine 5'-triphosphat e (GTP) and guanosine 5'-diphosphate (GDP) levels were measured using high- performance liquid chromatography, Trovafloxacin at concentrations of 2 and 1 mg/mL reduced the intracellular ATP content from 12.5 +/- 1.7 to 1.9 +/- 0.3 nmol/10(6) cells and 9.3 +/- 0.8 nmol/10(6) cells, respectively, withi n 60 min. In addition, ADP, GTP and GDP levels were extensively depleted. L evofloxacin at concentrations of 5 and 2.5 mg/mL led to a significant ATP d ecline from 12.5 +/- 1.7 to 2.3 +/- 0.2 nmol/10(6) cells and 10.3 +/- 0.9 n mol/10(6) cells, respectively, within 60 min. These data indicate that infu sions of high doses of trovafloxacin or levofloxacin are not compatible wit h maintenance of endothelial cell function. Commercial preparations have to be diluted and should be administered into large veins.