Abstract: Introduction Urosal® is one of the drugs available in Poland for the prevention and treatment of urinary tract infections (UTI). It contains the combination of antimicrobial methenamine and phenyl salicylate with analgesic and with anti-inflammatory activity. Aim The aim of the study was to evaluate the susceptibility to Urosal® of selected model bacterial type strains, including antibiotics resistant strains. Material and methods The method of microdilution in culture broth, as well as the method of in vitro activity evaluation in artificial urine were used in the course of research. The composition of artificial urine resembled natural urine. Results The obtained results indicate the potential ability of methenamine with phenyl salicylate’s combination to inhibit both Gram-positive and Gram-negative bacteria, including Pseudomonas aeruginosa, which are common etiological factors of UTI. Conclusions The antibacterial activity of Urosal® confirmed in this preliminary in vitro study may be the basis for further research on bacterial type strains isolated from urinary tract infections.

Key words: bacteriological susceptibility evaluation, methenamine, urinary tract infection, Urosal®