In patients with cystic fibrosis (CF) lung damage secondary to chronic infection is the main cause of death. Treatment of lung disease to reduce the impact of infection, inflammation and subsequent lung injury is therefore of major importance. As Pseudomonas aeruginosa is the dominant pathogen in CF patients it has been the major target of all treatment strategies, possible antibiotic regimens and recommendations for years. More sophisticated antibiotic therapies introduced over the last decades have helped to improve the prognosis in cystic fibrosis, but then new multidrug-resistant pathogens emerged.