The role of levofloxacin in veterinary medicine currently

The third-generation fluoroquinolone antimicrobial agent levofloxacin (LVFX) has been in the focus of research in veterinary medicine recently. LVFX is being used in animals, including both registered (Argentina, China, India) and off-label formulations (USA). Although, it is restricted to human use only in the EU. The currently available scientific data from the veterinary field related to LVFX were summarized to evaluate the adequacy and appropriateness of the use of this antimicrobial agent in veterinary practice. The Scopus database (keywords: “levofloxacin” and “veterinary”) research articles and articles referenced by them were used as information sources. Thirty-eight research articles on LVFX pharmacokinetics in mammals and birds, 8 tissue depletion articles, and 84 articles referring to the antimicrobial activity (in vivo and in vitro) of LVFX against microorganisms isolated from animals and their habitats were found and analyzed. Broad antimicrobial activity spectrum, favorable for once-daily administration, pharmacokinetic properties, short depletion time in edible tissues, and legal use in veterinary medicine outside the EU speak in favor of LVFX. However, microorganism isolates from companion and farm animals also revealed resistance to LVFX, e.g., Clostridium difficile, Escherichia coli and Staphylococcus pseudintermedius. These findings limit the potential of LVFX in veterinary medicine. Independently of the legal status of LVFX in different countries, it is used in veterinary medicine in the biggest countries in the world. It could not be omitted that microbial resistance could spread across the borders, and the inadequate LVFX use can have an impact on antimicrobial efficacy and global health. Therefore, pharmacokinetic-pharmacodynamic studies are demanded to establish the correct and safe LVFX dosing regimen for each single animal species.