and will vary with the age weight and response of the particular individual the above dosages are exemplary of the average case there can of course be individual instances where higher or lower dosage ranges are merited and such are within the scope of this invention it is preferred that the dosage is selected to modulate metabolism of the bacteria in such a way as to inhibit or stop growth of said bacteria or by killing said bacteria the skilled artisan may identify this amount as provided herein as well as using other methods known in the art e g by the application mic tests a further embodiment of the invention provides for the contacting step of the methods to further comprise contacting an in dwelling device in a patient in dwelling devices include but are not limited to surgical implants prosthetic devices and catheters i e devices that are introduced to the body of an individual and remain in position for an extended time such devices include for example artificial joints heart valves pacemakers vascular grafts vascular catheters cerebrospinal fluid shunts urinary catheters and continuous ambulatory peritoneal dialysis capd catheters a gemifloxacin compound or composition of the invention may be administered by injection to achieve a systemic effect against relevant bacteria preferably a maxillary sinus pathogenic bacteria shortly before insertion of an in dwelling device treatment may be continued after surgery during the in body time of the device in addition the composition.