Question 20

Has the role of fluoroquinolones such as levofloxacin in treating RTI changed over the last decade and what do you expect its role to be in the next ten years?

Our knowledge of pharmacodynamics and pharmacokinetics of the fluoroquinolones has changed dramatically over the last decade. We have learned that these agents are potent concentration-dependent bactericidal agents and as such, should be dosed at the highest tolerated dose given once daily. The additional benefit of this improved dosing is that the duration of therapy can be shortened to as low as 5 days for CAP and ABECB. Because the safety profile of levofloxacin is so favourable, it is the only respiratory fluoroquinolone that is capable of this improved dosing scheme. The 750 mg dose is now the appropriate dose for these indications as well as hospital-acquired pneumonia (HAP). Given the excellent tolerability of the drug and its’ spectrum against the majority of respiratory pathogens involved in ABECB, CAP and HAP, fluoroquinolones in general and levofloxacin, in particular, will be widely used agents for the foreseeable future unless important bacterial resistance emerges. In the future, I believe even higher doses of levofloxacin (1,000 mg given once daily) may be utilized for these indications. Higher doses (assuming good patient tolerance) may yield even better bacterial killing, rapid patient clinical responses, and, hopefully, less emergence of bacterial resistance.