Aim. To study medical and environmental safety of antibacterial therapy of lower excretory tract infections (urinary tract infections), which is one of the important components of curbing antibiotic resistance of the microbiota at the global and local levels. When issuing clinical recommendations for the treatment of infectious and inflammatory diseases of the urogenital tract, experts should take into account the following factors justifying antibacterial therapy regimens: a) pharmacokinetics, b) the natural activity of the antibiotic against topical uropathogens and their level of acquired resistance in the region, c) environmental safety, taking into account the complications of antibacterial therapy. We performed antibacterial therapy in 102 patients of the older age group (average age 70.5±2.5 years) with chronic bacterial prostatitis. The patients were divided into two groups: the main group and the comparison group. Patients in the main group received fluoroquinolone levofloxacin, while patients in the comparison group were treated with standard antibiotics. As a result of the therapy, it was found that environmentally unfavuorable effects with the selection of resistant strains of microorganisms were noted in patients of the comparison group who had received empirical therapy for a long time. The antibacterial efficacy of fluoroquinolones was found to be significantly better and the antibiotic resistance of uropathogens was found to be about 16.5–18 %. The results obtained can be explained by the facts that patients had not received fluoroquinolones before and that antibiotic resistance is due to prolonged use of antibacterial drugs: this increases the resistance of microorganisms and creates difficulties in etiotropic therapy of patients. © 2025 Elsevier B.V., All rights reserved.