The drug has a wide spectrum of antimicrobial action against gram-positive microorganisms (Enterococcus spp., Listeria monocytogenes, Staphylococcus spp. (including Staphylococcus aureus), Streptococcus spp.), gram-negative microorganisms (Campylobacter spp., Enterobacter spp., Escherichia coli, Haemophilus spp. ., Klebsiella spp., Pasteurella spp., Proteus spp., Pseudomonas spp., Salmonella spp.), anaerobic microorganisms (Clostridium perfringens, Fusobacterium necrophorum), as well as Bordetella spp., Chlamydia spp., Mycobacterium spp., Mycoplasma spp., Ricketsia spp.
After long-term use of the drug, microorganisms do not develop resistance to it. The drug is effective against pathogens resistant to tetracyclines, aminoglycosides, macrolides, amphenicols, sulfonamides and trimethoprim.
The mechanism of action is associated with blockade of DNA gyrase (topoisomerase II) and topoisomerase IV, disruption of supercoiling and cross-linking of deoxyribonucleic acid breaks, inhibition of deoxyribonucleic acid synthesis, profound metabolic changes in the cytoplasm, cell wall and membranes.
When administered orally, the drug is well and quickly absorbed from the gastrointestinal tract and, entering the blood, penetrates all organs and tissues of the body. Feed intake has little effect on the speed and completeness of absorption. The bioavailability of levofloxacin after oral administration is 99%, the concentration in the blood serum reaches a maximum 2 hours after administration, the half-life is about 7 hours. Levofloxacin penetrates well into organs and tissues: lungs, bronchial mucosa, sputum, genitourinary organs, polymorphonuclear leukocytes, alveolar macrophages. It is excreted from the body primarily by the kidneys by glomerular filtration or tubular secretion. After oral administration, it is mainly excreted unchanged in urine within 48 hours. If liver and kidney function are impaired, the elimination period may be increased.
