Fluoroquinolones: mechanism of action, classification, and development of resistance.

The fluoroquinolones represent an evolving class of broad-spectrum antimicrobial agents used in the prevention and treatment of a variety of ocular infections; however, resistance to currently available agents in the class has been emerging among ocular pathogens. This article reviews the mechanism of action of existing and new fluoroquinolones and discusses the structure-activity relationship of the fluoroquinolones as it relates to the classification of these compounds. This article also highlights the mechanism of resistance among common ocular pathogens and discusses the potential need for newer fluoroquinolones in ophthalmology.