In this long, but well written paper from the CDC, there are a few clear suggestions for using fluoroquinolones that make good sense:
1) for most gram-negative infections of the skin and urinary tract, including P. aeruginosa infections, ciprofloxacin monotherapy is appropriate.
2) Ciprofloxacin, levofloxacin, and gatifloxain all achieve high concentrations in urine; thus, they would all be appropriate choices for treating urinary tract infections in the community. Ciprofloxacin would be the most appropriate therapy in cases where P. aeruginosa is a known or suspected pathogen. For other gram-negative infections, levofloxacin or gatifloxacin should be prescribed in appropriate doses to surpass the mutant prevention concentrations at the infection site.
3) For infections in which S. pneumoniae is anticipated to be the most likely pathogen (e.g., community-acquired pneumonia), moxifloxacin, which currently has the best antipneumococcal pharmacodynamic activity and the lowest mutant prevention concentrations against this organism, would represent a prudent therapeutic choice.
4) By contrast, levofloxacin MIC90s against S. pneumoniae are significantly higher than those of moxifloxacin and gatifloxacin. Levofloxacin is therefore not an appropriate choice for respiratory infections.