The aim of the stııdy was to determine the effects of levotloxacin on the phagocytic and intracellular killing functions of hıtmun neutrophils at different therapeutic concentrations and to investigate the possible differences between püre powder and pharmaceutical form of Icvotlo.vacin on the neutrophil fımctions. Neutrophils obtained from healthv volunteers were incubated with both püre poM’der and pharmaceutical form of levofloxacin at different concentrations (1.4 pg/mL, 2.8 ııg mİ.. 5.7 pg/mL, 11.4 ııg mİ.i. At concentrations of 2.8 pg/mL Solutions, prepared from both püre powder and pharmaceutical form of Icvotlo.vacin. were obsen’ed to decrease phagocvtosis and intracellular killing comparing to control samples, but onlv the decrease for the pharmaceutical form ’s effect on phagocytic function w as statisticallv signifıcant (p<0.05). At concentration of 2.8 pg/mL solution, prepared from pharmaceutical form of levofloxacin, was obsen’ed to statisticallv signifıcant decrease phagocvtosis comparing to 2.8 pg/mL solution prepared from püre powder of levofloxacin (p<0.05). At concentration of 5.7 pg/mL solution, prepared from pharmaceutical form of levofloxacin, was obsen’ed to statisticallv signifıcant decrease phagocvtosis and intracellular killing comparing to 5.7 pg/mL solution prepared from püre powder of levofloxacin (p<0.05). Phagocytic activitv of neutrophils w as signifıcantly decreased bv levofloxacin solution prepared from püre powder at concentrations of 11.4 pg/mL when compared with control (p<0.05). As conclusion, the Solutions prepared with pharmaceutical form ha\’e signifıcantly inhibition on the phagocytic and intracellular killing functions of human neutrophils in vitro when comparing with the Solutions prepared with püre powder.

Keywords: Phagocvtosis, intracellular killing, Levojloxacin, Neutrophil.