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(gat i FLOKS a sin)

Dosage Forms

Excipient information presented when available (limited, particularly for generics); consult specific product labeling.

Solution, Ophthalmic:

Zymaxid: 0.5% (2.5 mL) [contains benzalkonium chloride, edetate disodium]

Generic: 0.5% (2.5 mL)

Brand Names: U.S.

  • Zymaxid

Pharmacologic Category

  • Antibiotic, Fluoroquinolone
  • Antibiotic, Ophthalmic


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.


Ophthalmic: Not measurable (<5 ng/mL)

Use: Labeled Indications

Treatment of bacterial conjunctivitis


Zymaxid: There are no contraindications listed in the manufacturer’s labeling.

Zymar [Canadian product]: Hypersensitivity to gatifloxacin, other quinolones, or any component of the formulation

Dosing: Adult

Bacterial conjunctivitis: Ophthalmic:

Zymar [Canadian product]:

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) 4 times/day while awake


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

Dosing: Geriatric

Refer to adult dosing.

Dosing: Pediatric

Bacterial conjunctivitis: Children ≥1 year: Ophthalmic: Refer to adult dosing.

Dosing: Renal Impairment

No dosage adjustment provided in manufacturer’s labeling. However, dosage adjustment unlikely due to low systemic absorption.

Dosing: Hepatic Impairment

No dosage adjustment provided in manufacturer’s labeling. However, dosage adjustment unlikely due to low systemic absorption.


For topical ophthalmic use only; avoid touching tip of applicator to eye, fingers, or other surfaces.


Store between 15°C to 25°C (59°F to 77°F); do not freeze.

Drug Interactions

There are no known significant interactions.

Test Interactions

Some quinolones may produce a false-positive urine screening result for opioids 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 opioid screens by more specific methods should be considered.

Adverse Reactions

1% to 10%:

Cardiovascular: Edema

Dermatologic: Contact dermatitis, erythema

Gastrointestinal: Dysgeusia

Ophthalmic: Conjunctival irritation, decreased visual acuity, eye discharge, eye irritation, eye pain, increased lacrimation, keratitis, ocular edema, papillary conjunctivitis, xerophthalmia

Respiratory: Rhinorrhea

<1% (Limited to important or life-threatening): Angioedema, blepharitis (allergic), blurred vision, chemosis, conjunctival hemorrhage, corneal deposits, corneal disease, corneal opacity (subepithelial), corneal ulcer, cyst (conjunctival), dermatitis, dizziness, endophthalmitis, eye redness, iritis, keratoconjunctivitis, macular edema, nausea, oral paresthesia, photophobia, pruritus, sore throat, tinnitus, tremor, urticaria, uveitis


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.

Monitoring Parameters

Signs of infection

Pregnancy Risk Factor


Pregnancy Considerations

Adverse events were observed in some animal reproduction studies. Systemic concentrations of gatifloxacin following ophthalmic administration are below the limit of quantification. If ophthalmic agents are needed during pregnancy, the minimum effective dose should be used in combination with punctual occlusion for 3 to 5 minutes after application to decrease potential exposure to the fetus (Samples 1988).

Patient Education

• Discuss specific use of drug and side effects with patient as it relates to treatment. (HCAHPS: During this hospital stay, were you given any medicine that you had not taken before? Before giving you any new medicine, how often did hospital staff tell you what the medicine was for? How often did hospital staff describe possible side effects in a way you could understand?)

• Patient may experience bad taste. Have patient report immediately to prescriber vision changes, eye pain, severe eye irritation, or eye or eyelid edema (HCAHPS).

• Educate patient about signs of a significant reaction (eg, wheezing; chest tightness; fever; itching; bad cough; blue skin color; seizures; or swelling of face, lips, tongue, or throat). Note: This is not a comprehensive list of all side effects. Patient should consult prescriber for additional questions.

Intended Use and Disclaimer: Should not be printed and given to patients. This information is intended to serve as a concise initial reference for healthcare professionals to use when discussing medications with a patient. You must ultimately rely on your own discretion, experience and judgment in diagnosing, treating and advising patients.