Zymaxid®

Gatifloxacin 0.5% · ophthalmic solution

Antibiotic

Approved uses

Bacterial conjunctivitis

Day 1: 1 drop in the affected eye(s) every 2 hours while awake, up to 8 times. Days 2 through 7: 1 drop 2 to 4 times daily while awake.

FDA label, Indications and Usage (1) and Dosage and Administration (2). Trial: Heller W, Cruz M, Bhagat YR, et al. Gatifloxacin 0.5% administered twice daily for the treatment of acute bacterial conjunctivitis in patients one year of age or older. J Ocul Pharmacol Ther. 2014;30(10):815-822.

Contraindications

History of hypersensitivity to gatifloxacin, to other quinolones, or to any component of this product.

Available Forms

2.5 mL in a 5 mL bottle, 0.5% solution, 5 mg gatifloxacin per mL

Mechanism of Action

8-methoxyfluoroquinolone with a 3-methylpiperazinyl substituent at C7; antibacterial action follows inhibition of DNA gyrase, which replicates, transcribes and repairs bacterial DNA, and of topoisomerase IV, which partitions chromosomal DNA at cell division. Those targets differ from those of aminoglycoside, macrolide and tetracycline antibiotics, so no cross-resistance with those classes exists, although cross-resistance between systemic gatifloxacin and some other fluoroquinolones has been observed.

Warnings & Precautions

Hypersensitivity reactions: Anaphylaxis, angioedema (pharyngeal, laryngeal or facial), dyspnea, urticaria and itching have occurred in patients receiving this drug topically, some after a single dose, and rare Stevens-Johnson syndrome has been reported with topical ophthalmic use; discontinue if an allergic reaction occurs.
Resistant organism overgrowth: Prolonged use may allow overgrowth of nonsusceptible organisms including fungi; if superinfection occurs, discontinue and start alternative therapy, examining with slit lamp and fluorescein where appropriate.
Corneal endothelial cell injury: May result if the solution is introduced directly into the anterior chamber; for topical ophthalmic use only.

Common Side Effects

Ocular, at least 1%: Worsening of conjunctivitis, eye irritation, eye pain (N = 717 treated in the clinical studies).
Nonocular, at least 1%: Dysgeusia.
Other formulations, not this product: Chemosis, conjunctival hemorrhage, dry eye, eye discharge, eyelid edema, increased lacrimation, keratitis, red eye, papillary conjunctivitis, reduced visual acuity, headache, all reported in studies of other gatifloxacin ophthalmic solutions rather than this one.
Postmarketing, frequency not estimable: Anaphylaxis, angioedema (pharyngeal, oral or facial), dyspnea, blepharitis, eye pruritus, eye swelling including corneal and conjunctival edema, allergic dermatitis, blurred vision, nausea, pruritus, rash, urticaria.

Pregnancy & Lactation

Pregnancy: No available data in pregnant women to inform drug-associated risk. Oral dosing in rats and rabbits through organogenesis produced no adverse developmental outcomes at clinically relevant doses; teratogenic effects in rat fetuses (skeletal and craniofacial malformations, delayed ossification, atrial enlargement, reduced fetal weight) appeared at 150 mg/kg/day and above, roughly 600-fold the maximum recommended human ophthalmic dose on a mg/m2 basis, with no teratogenic effects in either species up to 50 mg/kg/day. A perinatal and postnatal rat study showed increased late gestation fetal loss and neonatal mortality only at 200 mg/kg/day, roughly 800-fold the ophthalmic dose.

Lactation: No information on presence in human milk, effects on the breastfed infant, or effects on milk production. Found in rat milk after oral dosing, though systemic levels after topical ocular use are low.

Pediatric Use

Not established below 1 year; safe and effective at 1 year and older.