Intracellular Activity 

Intracellular accumulation and activity of antimicrobials is important not only for obligate or facultative intracellular bacteria (e.g., mycoplasmas, salmonellas) but also for any pathogenic bacteria to be phagocytized by polymorphonuclear leukocytes. Studies of several animal species have shown that intracellular concentrations of Enrofloxacin largely exceed those of the extracellular, interstitial fluids and that such concentrations actively kill intracellular bacteria.

The high concentrations of Enrofloxacin in polymorphonuclear leukocytes support the favourable kinetics by carrying the active ingredient to the site of infection, enhancing intracellular killing of ingested bacteria.

In addition, enrofloxacin does not impair, but rather it stimulates phagocytic activity ("respiratory burst activity") of polymorphonuclear leukocytes.

Because Baytril shows no adverse effects on the immune system, Baytril can be used simultaneously with vaccines or in combination with vaccination programmes without adversely affecting the immune response.