Erythromycin Ointment
erythromycin 0.5% · ophthalmic ointment
Antibiotic
Approved uses
Superficial ocular infection of the conjunctiva or cornea
About 1 cm ribbon to the infected eye(s) up to 6 times daily depending on severity
Its class raises treatment-related ocular complications about fourfold, unlike fluoroquinolones.
Ophthalmia neonatorum prophylaxis (Neisseria gonorrhoeae, Chlamydia trachomatis)
1 cm ribbon into each lower conjunctival sac, not flushed afterward, new tube per infant
Cuts conjunctivitis of any cause by about a third at 1 month, but chlamydial protection is unproven.
OFF-LABELNot in the FDA label for this product
Anterior blepharitis
Ribbon to the eyelid margins one or more times daily or QHS for a few weeks
Cochrane · no cure shown
Cochrane review of 34 studies (2169 participants) found topical antibiotics gave some symptomatic relief and were effective in eradicating bacteria from the eyelid margin in anterior blepharitis, but the authors concluded there is no strong evidence that any treatment cures chronic blepharitis. Off-label because this label covers the conjunctiva and cornea only, not the lid margin.
Contraindications
History of hypersensitivity to erythromycin.
Available Forms0.5% (5 mg/g) ointment, 3.5 g tube, 1 g tube in cartons of 50
Mechanism of ActionMacrolide that binds reversibly to the bacterial 50S ribosomal subunit and inhibits protein synthesis without affecting nucleic acid synthesis; generally bacteriostatic. Covers streptococci, Staphylococcus aureus including penicillinase-producing strains, Chlamydia trachomatis, and Neisseria gonorrhoeae, while methicillin-resistant staphylococci are uniformly resistant.
Warnings & Precautions
- Superinfection: Antimicrobial use may allow overgrowth of nonsusceptible organisms including fungi, which requires stopping the antibiotic.
- Penicillinase-producing gonococci: Effectiveness in preventing ophthalmia caused by penicillinase-producing Neisseria gonorrhoeae is not established.
- Maternal gonorrhea: For infants born to mothers with clinically apparent gonorrhea, topical prophylaxis alone is inadequate and IV or IM aqueous crystalline penicillin G is indicated, a single 50,000 unit dose for term infants or 20,000 units for low birth weight infants.
Common Side Effects
- Ocular, most frequent: Minor irritation and redness.
- Hypersensitivity: Reactions are also among the most frequently reported, with no rate given in the label.
Pregnancy & LactationPregnancy: Reproduction studies in rats, mice, and rabbits at several multiples of the usual human dose showed no evidence of fetal harm; there are no adequate and well-controlled studies in pregnant women, so use only if clearly needed.
Lactation: Caution advised in nursing women; the label gives no milk transfer or infant safety data.
Pediatric UseIndicated in newborns for ophthalmia neonatorum prophylaxis; the pediatric section adds no separate limits.