Tissue Plasma Saliva Blister fluid Bronchial mucosa Alveolar macrophages Epithelial lining fluid Maxillary sinus Ethmoid sinus Nasal polyps Interstitial fluid Female genital tract* * intravenous administration of a 1 10 h after administration 2 unbound concentration 3 from 3 h up to 36 h post dose 4 at the end of infusion