Levofloxacin is an advanced generation fluoroquinolone antibiotic. Levofloxacin was launched in the Japanese market in 1993, and thus has had more than 13 years of testing in efficacy and safety globally. Chemically, levofloxacin is the S-enantiomer (L-isomer) of ofloxacin, and has approximately twice the potency of ofloxacin, because the R+enantiomer (D-isomer) of ofloxacin is essentially inactive. In addition, the S-enantiomer (L-isomer) of ofloxacin, has substantially less toxicity. Like other fluoroquinolines, it works by inhibiting DNA gyrase, an enzyme that negatively supercoils DNA.

Levofloxacin is effective against a number of gram-positive and gram-negative bacteria. Because of its broad spectrum of action, levofloxacin is frequently prescribed empirically for a wide range of infections (e.g. pneumonia, urinary tract infection) before the specific causal organism is known. If the causal organism is identified, levofloxacin may be discontinued and the patient may be switched to an antibiotic with a narrower spectrum of activity. Levofloxacin is currently the only respiratory fluoroquinolone approved by the U.S. FDA for the treatment of nosocomial pneumonia.

Gram-positive bacteria

    * Enterococcus faecalis (many strains are only moderately susceptible)
    * Staphylococcus aureus (methicillin-susceptible strains)
    * Staphylococcus epidermidis (methicillin-susceptible strains)
    * Staphylococcus saprophyticus
    * Streptococcus pneumoniae (including Multidrug-resistant strains, MDRSP)
    * Streptococcus pyogenes

Gram-negative bacteria

    * Enterobacter cloacae
    * Klebsiella pneumoniae
    * Pseudomonas aeruginosa
    * Escherichia coli
    * Legionella pneumophila
    * Serratia marcescens
    * Haemophilus influenzae
    * Moraxella catarrhalis
    * Haemophilus parainfluenzae
    * Proteus mirabilis
    * Campylobacter

Before taking any prescription medicine, it is important that you consult your doctor!