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Pronunciation
(gat i FLOKS a sin)
Generic Available (U.S.)
No
Brand Names: U.S.
Brand Names: Canada
Pharmacologic Category
Pharmacologic Category Synonyms
Use: Labeled Indications
Treatment of bacterial conjunctivitis
Pregnancy Risk Factor
C
Pregnancy Considerations
Gatifloxacin has been shown to be fetotoxic in animal studies. Quinolone exposure during human pregnancy has been reported with other agents (refer to Ciprofloxacin (Systemic), Ofloxacin (Systemic), and Norfloxacin monographs). Following ophthalmic administration, serum concentrations of gatifloxacin are below the limits of quantification (<5 ng/mL). Systemic absorption would be required in order for gatifloxacin to cross the placenta.
Lactation
Excretion in breast milk unknown/use caution
Breast-Feeding Considerations
Other quinolones are known to be excreted in breast milk. The manufacturer recommends using caution if gatifloxacin is administered while nursing.
Contraindications
Zymar®: Hypersensitivity to gatifloxacin, other quinolone antibiotics, or any component of the formulation
Zymaxid™: There are no contraindications listed in the manufacturer's labeling.
Warnings/Precautions
Concerns related to adverse effects:
• Hypersensitivity reactions: Severe hypersensitivity reactions, including anaphylaxis, have occurred with systemic quinolone therapy. The spectrum of these reactions can vary widely; reactions may present as typical allergic symptoms (eg, itching, urticaria, rash, edema) after a single dose, or may manifest as severe idiosyncratic dermatologic (eg, Stevens-Johnson, toxic epidermal necrolysis), vascular (eg, vasculitis), pulmonary (eg, pneumonitis), renal (eg, nephritis), hepatic (eg, hepatic failure or necrosis), and/or hematologic (eg, anemia, cytopenias) events, usually after multiple doses. Prompt discontinuation of drug should occur if skin rash or other symptoms arise.
• Superinfection: Prolonged use may result in fungal or bacterial superinfection.
Special populations:
• Contact lens wearers: Contact lenses should not be worn during treatment of ophthalmic infections.
Dosage form specific issues:
• Ophthalmic solution: For topical ophthalmic use only. Do not inject ophthalmic solution subconjunctivally or introduce directly into the anterior chamber of the eye.
Adverse Reactions
1% to 10%:
Central nervous system: Headache
Gastrointestinal: Taste disturbance
Ocular: Chemosis, conjunctival hemorrhage, conjunctival irritation, discharge, dry eye, edema, irritation, keratitis, lacrimation increased, pain, papillary conjunctivitis, visual acuity decreased
Metabolism/Transport Effects
None known.
Drug Interactions
There are no known significant interactions.
Storage
Store between 15°C to 25°C (59°F to 77°F); do not freeze.
Mechanism of Action
Gatifloxacin is a DNA gyrase inhibitor, and also inhibits topoisomerase IV. DNA gyrase (topoisomerase II) is an essential bacterial enzyme that maintains the superhelical structure of DNA. DNA gyrase is required for DNA replication and transcription, DNA repair, recombination, and transposition; inhibition is bactericidal.
Pharmacodynamics/Kinetics
Absorption: Ophthalmic: Not measurable (<5 ng/mL)
Dosage
Ophthalmic: Children ≥1 year and Adults: Bacterial conjunctivitis:
Zymar®:
Days 1 and 2: Instill 1 drop into affected eye(s) every 2 hours while awake (maximum: 8 times/day)
Days 3-7: Instill 1 drop into affected eye(s) up to 4 times/day while awake
Zymaxid™:
Day 1: Instill 1 drop into affected eye(s) every 2 hours while awake (maximum: 8 times/day)
Days 2-7: Instill 1 drop into affected eye(s) 2-4 times/day while awake
Administration: Other
For topical ophthalmic use only; avoid touching tip of applicator to eye, fingers, or other surfaces.
Monitoring Parameters
Signs of infection
Test Interactions
Some quinolones may produce a false-positive urine screening result for opiates using commercially-available immunoassay kits. This has been demonstrated most consistently for levofloxacin and ofloxacin, but other quinolones have shown cross-reactivity in certain assay kits. Confirmation of positive opiate screens by more specific methods should be considered.
Patient Education
Tilt head back and instill prescribed number of drops in affected eye as often as directed for length of time prescribed. Do not allow dropper to touch any surface, including the eyes or hands. Apply light pressure to the inside corner of the eye (near the nose) after each drop. Avoid wearing contact lenses during treatment. May cause headache or dizziness. May cause temporary eye discomfort (stinging, burning, itching, pain, tearing) or a bad taste in mouth after instillation. Report persistent adverse reactions, visual disturbances, or if condition worsens. If you experience signs of allergic reaction (eg, itching, rash, respiratory difficulty, facial edema, difficulty swallowing), discontinue use immediately and report to prescriber.
Geriatric Considerations
Evaluate the patient's or caregiver's ability to safely administer the correct dose of ophthalmic medication.
Dental Health: Effects on Dental Treatment
Key adverse event(s) related to dental treatment: Taste disturbance.
Dental Health: Vasoconstrictor/Local Anesthetic Precautions
Gatifloxacin is one of the drugs confirmed to prolong the QT interval and is accepted as having a risk of causing torsade de pointes. The risk of drug-induced torsade de pointes is extremely low when a single QT interval prolonging drug is prescribed. In terms of epinephrine, it is not known what effect vasoconstrictors in the local anesthetic regimen will have in patients with a known history of congenital prolonged QT interval or in patients taking any medication that prolongs the QT interval. Until more information is obtained, it is suggested that the clinician consult with the physician prior to the use of a vasoconstrictor in suspected patients, and that the vasoconstrictor (epinephrine, mepivacaine and levonordefrin [Carbocaine® 2% with Neo-Cobefrin®]) be used with caution.
Dental Comment
Gatifloxacin is known to prolong the QT interval. The QT interval is measured as the time and distance between the Q point of the QRS complex and the end of the T wave in the ECG tracing. After adjustment for heart rate, the QT interval is defined as prolonged if it is more than 450 msec in men and 460 msec in women. A long QT syndrome was first described in the 1950s and 60s as a congenital syndrome involving QT interval prolongation and syncope and sudden death. Some of the congenital long QT syndromes were characterized by a peculiar electrocardiographic appearance of the QRS complex involving a premature atria beat followed by a pause, then a subsequent sinus beat showing marked QT prolongation and deformity. This type of cardiac arrhythmia was originally termed “torsade de pointes” (translated from the French as “twisting of the points”). Gatifloxacin is considered as having a risk of causing torsade de pointes. Since it is not known what effect vasoconstrictors in the local anesthetic regimen will have in patients with a known history of congenital prolonged QT interval or in patients taking any medication that prolongs the QT interval, a medical consult is suggested.
Mental Health: Effects on Mental Status
Gatifloxacin may cause dizziness, insomnia; may rarely produce abnormal thinking, agitation, anorexia, anxiety, asthenia, ataxia, confusion, depersonalization, depression, euphoria, hallucination, hostility, nervousness, panic attacks, paranoia, psychosis, somnolence, or stress
Mental Health: Effects on Psychiatric Treatment
May have potential to prolong QT interval; should avoid in patients with uncorrected hypokalemia, or concurrent administration of other medications known to prolong the QT interval (antipsychotics, tricyclic antidepressants, ziprasidone)
Dosage Forms
Excipient information presented when available (limited, particularly for generics); consult specific product labeling. [DSC] = Discontinued product
Solution, ophthalmic [drops]:
Zymar®: 0.3% (5 mL [DSC]) [contains benzalkonium chloride]
Zymaxid™: 0.5% (2.5 mL) [contains benzalkonium chloride]
Pricing: U.S. (www.drugstore.com)
Solution (Zymaxid)
0.5% (2.5): $96.89
References
Straley CM, Cecil EJ, and Herriman MP, “Gatifloxacin Interference With Opiate Urine Drug Screen,” Pharmacotherapy, 2006, 26(3):435-9.
International Brand Names
Lexi-Comp.com
Last full review/revision January 2012
Content last modified January 2012
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