Brands, Medical Use, Clinical Data
Drug Category
Dosage Forms
Brands / Synonyms
Factive; Gemifloxacin mesilate
Indications
For the treatment of bacterial infection caused by susceptible strains such as S. pneumoniae, H. influenzae, H. parainfluenzae, or M. catarrhalis, S. pneumoniae (including multi-drug resistant strains [MDRSP]), M. pneumoniae, C. pneumoniae, or K. pneumoniae.
Pharmacology
Gemifloxacin is a quinolone/fluoroquinolone antibiotic. Gemifloxacin is bactericidal and its mode of action depends on blocking of bacterial DNA replication by binding itself to an enzyme called DNA gyrase, which allows the untwisting required to replicate one DNA double helix into two. Notably the drug has 100 times higher affinity for bacterial DNA gyrase than for mammalian. Gemifloxacin is a broad-spectrum antibiotic that is active against both Gram-positive and Gram-negative bacteria.
Mechanism of Action
The bactericidal action of gemifloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, and recombination.
Absorption
Rapidly absorbed from the gastrointestinal tract. The absolute bioavailability averages approximately 71%.
Toxicity
Not Available
Biotrnasformation / Drug Metabolism
Gemifloxacin is metabolized to a limited extent by the liver. All metabolites formed are minor (<10% of the administered oral dose); the principal ones are N-acetyl gemifloxacin, the E-isomer of gemifloxacin and the carbamyl glucuronide of gemifloxacin.
Contraindications
Gemifloxacin is contraindicated in patients with a history of hypersensitivity to gemifloxacin,
fluoroquinolone antibiotic agents, or any of the product components.
Drug Interactions
Administration of repeat doses of FACTIVE had no effect on the repeat dose pharmacokinetics of
theophylline, digoxin or an ethinylestradiol/levonorgestrol oral contraceptive product in healthy subjects.
Concomitant administration of FACTIVE and calcium carbonate, cimetidine, omeprazole, or an
estrogen/progesterone oral contraceptive produced minor changes in the pharmacokinetics of gemifloxacin, which were
considered to be without clinical significance.
Concomitant administration of FACTIVE with probenecid resulted in a 45% increase in systemic exposure
to gemifloxacin.
FACTIVE had no significant effect on the anticoagulant effect of warfarin in healthy subjects on
stable warfarin therapy. However, because some quinolones have been reported to enhance the anticoagulant effects of
warfarin or its derivatives in patients, the prothrombin time or other suitable coagulation test should be closely
monitored if a quinolone antimicrobial is administered concomitantly with warfarin or its derivatives.
Quinolones form chelates with alkaline earth and transition metals. The absorption of oral
gemifloxacin is significantly reduced by the concomitant administration of an antacid containing aluminum and
magnesium. Magnesium- and/or aluminum-containing antacids, products containing ferrous sulfate (iron), multivitamin
preparations containing zinc or other metal cations, or Videx (didanosine) chewable/buffered tablets or the pediatric
powder for oral solution should not be taken within 3 hours before or 2 hours after FACTIVE. Sucralfate should not be
taken within 2 hours of FACTIVE.
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