Levofloxacin

Levofloxacin is a fluoroquinolone antibiotic and the optical S-(-) isomer of racemic ofloxacin. It reportedly carries 8 to 128-fold more activity against both gram-negative and gram-positive bacteria compared to R-(+)-ofloxacin and remains stereochemically stable following administration (i.e. it does not invert to the inactive isomer). Levofloxacin, along with other quinolones such as gatifloxacin and moxifloxacin, is a member of the third generation of fluoroquinolones, colloquially referred to as the "respiratory quinolones" due to improved activity against gram-positive bacteria commonly implicated in respiratory infections.

Levofloxacin was first approved by the FDA in 1996, and was approved in Canada and several South American countries soon after.

In oral and intravenous formulations, levofloxacin is indicated in adults for the treatment of various infections caused by susceptible bacteria, including infections of the upper respiratory tract, lower respiratory tract, skin, skin structures, urinary tract, and prostate. The oral formulation is also indicated in both adults and children 6 months of age and older for the post-exposure management of inhalational anthrax caused by Bacillus anthracis and for the treatment and/or prophylaxis of plague caused by Yersinia pestis.

In its ophthalmic formulation, levofloxacin is indicated for the treatment of bacterial conjunctivitis caused by susceptible organisms. An inhalational solution available in Canada is indicated for the management of cystic fibrosis patients aged 18 years or older with chronic pulmonary Pseudomonas aeruginosa infections.