Levofloxacin, like other fluoroquinolones, acts as a antibacterial agent on bacterial topoisomerases. A broad range of Gram-positive and Gram-negative of levofloxacin was confirmed in clinical trials in patients with respiratory tract infections. In therapy of chronic diseases exacerbations of the respiratory tract, including community-acquired pneumonia, a high oral bioavailability allows to switch from intravenous to oral way of treatment. Although a high penetration degree of levofloxacin into serum and tissues gives possibility to control bacterial biofilm. For this reasons levofloxacin is recommended for therapy of respiratory tract infections as a second-line antibacterial agent, but in severe exacerbations may be considered as additional therapy, rarely as monotherapy.