The present invention is related to pharmaceutical compositions capable of inhibiting or eliminating an infectious process caused by bacteria in warm-blooded animals. The present invention describes a stable formulation with a minimized methylpyrrolidone concentration. In order to reduce N-methylpyrrolidone concentration, a mixture was developed that eliminates the need to add preservatives and exhibiting a suitable viscosity and ensures the solubility of the composition when administered in drinking water at a ratio of dilution of up to 5,000 times in chlorinated or non-chlorinated water.
