The invention relates to a catheter for insertion into the body vessels, ducts and/or cavities, improved due to the use of a new nanoproduct useful in the prophylaxis, diagnostics and medicine, both human and veterinary. In particular, the invention relates to a catheter for insertion into the body vessels, ducts and/or cavities, for use in prophylaxis, diagnostics and medicine, both human and veterinary, made of plastic and coated with a protective lubricant layer, characterized in that it has an outer nanocoating of a biocompatible polymer capable of forming gel with water, permanently attached to said plastic either directly or through a nanocoating of a polymer chemically bonded to the catheter material and having antibacterial properties, wherein at least one of the nanocoatings comprises an addition of extracellular metabolites secreted by Lactobacillus reuteri DAN080 bacteria, said metabolites having antimicrobial and anti-inflammatory activity, as well as an optional addition of vitamin D in form of nanoparticles. Additional active agents selected from the group comprising chitosan alpha-ketoglutarate, chitosan citrate, chitosan lactate exhibiting antimicrobial and anti-inflammatory activity, small dicarboxilic acid, silver nanoparticles and vitamins D and E in the form of nanopowder coated with a protective coating, and the combinations thereof, are dispersed in the nanocoating made of biocompatible polymer and/or in the polymer having antibacterial properties. The invention also relates to a catheterization kit comprising a catheter as described above and a vial with water for injection (sterile), and a stress-reducing agent for oral administration in the form of live or heat inactivated L. reuteri DAN080 cultures, at a dose of 10 6 cells, for daily administration for the period of catheterization and/or at 8 hours prior to catheterization, or directly to the body cavity at 15 min. prior to catheterization
