indication

For the treatment of bronchitis, sinusitis, community-acquired pneumonia, and skin infections (abscesses, wounds) caused by S. pneumoniae, H. influenzae, S. aureus, M. pneumoniae, C. pneumoniae, L. pneumophila, S. pyogenes

pharmacology

Gatifloxacin is a synthetic broad-spectrum 8-methoxyfluoroquinolone antibacterial agent for oral or intravenous administration. 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. Gatifloxacin is a broad-spectrum antibiotic that is active against both Gram-positive and Gram-negative bacteria. It should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.

mechanism of action

The bactericidal action of Gatifloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, and recombination.

biotransformation

Gatifloxacin undergoes limited biotransformation in humans with less than 1% of the dose excreted in the urine as ethylenediamine and methylethylenediamine metabolites

absorption

Well absorbed from the gastrointestinal tract after oral administration with absolute bioavailability of gatifloxacin is 96%

half life

7-14 hours

drug interactions

Aluminium: Formation of non-absorbable complexes

Amiodarone: Increased risk of cardiotoxicity and arrhythmias

Bepridil: Increased risk of cardiotoxicity and arrhythmias

Bretylium: Increased risk of cardiotoxicity and arrhythmias

Chlorpromazine: Increased risk of cardiotoxicity and arrhythmias

Digoxin: Gatifloxacin increases the effect of digoxin

Dihydroquinidine barbiturate: Increased risk of cardiotoxicity and arrhythmias

Disopyramide: Increased risk of cardiotoxicity and arrhythmias

Fluphenazine: Increased risk of cardiotoxicity and arrhythmias

Iron: Formation of non-absorbable complexes

Iron Dextran: Formation of non-absorbable complexes

Magnesium: Formation of non-absorbable complexes

Magnesium oxide: Formation of non-absorbable complexes

Magnesium salicylate: Formation of non-absorbable complexes

Mesoridazine: Increased risk of cardiotoxicity and arrhythmias

Methotrimeprazine: Increased risk of cardiotoxicity and arrhythmias

Perphenazine: Increased risk of cardiotoxicity and arrhythmias

Prochlorperazine: Increased risk of cardiotoxicity and arrhythmias

Promazine: Increased risk of cardiotoxicity and arrhythmias

Promethazine: Increased risk of cardiotoxicity and arrhythmias

Propiomazine: Increased risk of cardiotoxicity and arrhythmias

Quinidine: Increased risk of cardiotoxicity and arrhythmias

Quinidine barbiturate: Increased risk of cardiotoxicity and arrhythmias

Quinupristin: This combination presents an increased risk of toxicity

Sotalol: Increased risk of cardiotoxicity and arrhythmias

Sucralfate: Formation of non-absorbable complexes

Tacrolimus: Additive QTc-prolongation may occur increasing the risk of serious ventricular arrhythmias. Concomitant therapy should be used with caution.

Thiethylperazine: Increased risk of cardiotoxicity and arrhythmias

Thioridazine: Increased risk of cardiotoxicity and arrhythmias

Thiothixene: May cause additive QTc-prolonging effects. Increased risk of ventricular arrhythmias. Consider alternate therapy. Thorough risk:benefit assessment is required prior to co-administration.

Toremifene: Additive QTc-prolongation may occur, increasing the risk of serious ventricular arrhythmias. Consider alternate therapy. A thorough risk:benefit assessment is required prior to co-administration.

Trifluoperazine: Increased risk of cardiotoxicity and arrhythmias

Triflupromazine: Increased risk of cardiotoxicity and arrhythmias

Trimipramine: Additive QTc-prolongation may occur, increasing the risk of serious ventricular arrhythmias. Concomitant therapy should be used with caution.

Voriconazole: Additive QTc prolongation may occur. Consider alternate therapy or monitor for QTc prolongation as this can lead to Torsade de Pointes (TdP).

Vorinostat: Additive QTc prolongation may occur. Consider alternate therapy or monitor for QTc prolongation as this can lead to Torsade de Pointes (TdP).

Zinc: Formation of non-absorbable complexes

Ziprasidone: Additive QTc-prolonging effects may increase the risk of severe arrhythmias. Concomitant therapy is contraindicated.