Penetration of ciprofloxacin into saliva and nasal secretions and effect of the drug on the oropharyngeal flora of ill subjects.

The pharmacokinetics of ciprofloxacin and its effect on the oropharyngeal bacterial flora were examined in 21 ill patients being treated for methicillin-resistant Staphylococcus aureus infections or colonization or both. Oral ciprofloxacin (750 mg twice a day) produced peak and trough concentrations in serum of 2.56 +/- 1.80 and 0.97 +/- 0.81 micrograms/ml and steady-state salivary and nasal secretory concentrations of 1.29 +/- 1.0 and 1.84 +/- 0.91 micrograms/ml, respectively. Because of technical problems, nasal secretory concentrations were felt to represent rough approximations of true values. Oral ciprofloxacin therapy did not promote colonization of the oropharynx by gram-negative bacilli.