Can erythromycin ophthalmic ointment be used to treat a corneal abrasion in a contact‑lens wearer?

Erythromycin Ophthalmic Ointment for Contact Lens-Related Corneal Abrasion

No, erythromycin ophthalmic ointment should not be used as monotherapy for a corneal abrasion in a contact lens wearer because it lacks antipseudomonal coverage, which is mandatory in this high-risk population. 1

Why Erythromycin Is Inadequate

Contact lens wearers require mandatory antipseudomonal antibiotic coverage with fluoroquinolones because Pseudomonas aeruginosa is the most common and devastating pathogen in this population. 1, 2

Key Limitations of Erythromycin

• Erythromycin ointments lack sufficient corneal penetration due to poor solubility, preventing them from achieving therapeutic tissue levels needed to prevent bacterial keratitis. 1

• Erythromycin has no activity against Pseudomonas aeruginosa, the organism responsible for rapidly progressive, sight-threatening keratitis in contact lens wearers. 1, 2

• Ointment formulations are inferior to drops for corneal abrasions because drops achieve higher corneal tissue concentrations and superior antimicrobial penetration. 1

Correct Treatment Approach

First-Line Therapy

Initiate topical fluoroquinolone drops within 24 hours of injury to prevent bacterial keratitis and ulceration. 1, 2

Recommended fluoroquinolone options:

• Moxifloxacin 0.5% one drop three times daily for 7 days 1
• Levofloxacin 1.5% one drop four times daily until epithelial healing is documented 1
• Ofloxacin 0.3% or ciprofloxacin 0.3% are FDA-approved alternatives 1

Critical Management Principles

• Never patch the eye in contact lens wearers because patching increases bacterial keratitis risk and does not improve pain. 1, 3

• Never place a therapeutic contact lens on a contact lens-related abrasion as this elevates secondary bacterial keratitis risk. 1, 2

• Immediately discontinue contact lens wear and do not resume until complete epithelial healing is confirmed by examination. 2, 3

Pain Management

• Use oral acetaminophen or NSAIDs for residual discomfort rather than relying on ointment for symptomatic relief. 1

• Topical NSAIDs (ketorolac 0.5%) can decrease pain, photophobia, and foreign body sensation when used as adjunctive therapy. 4

When to Escalate Treatment

Immediately refer to ophthalmology if any of these red flags develop:

• Central infiltrate >2mm (requires cultures before antibiotic initiation) 1
• Presence of hypopyon (layered white cells in anterior chamber) 1, 2
• Significant stromal involvement or corneal melting 1
• Increasing pain, purulent discharge, or worsening symptoms despite treatment 1, 2

Severe Keratitis Protocol

If bacterial keratitis develops, escalate to:

• Loading dose every 5-15 minutes, then hourly fluoroquinolone dosing 1, 2
• Consider fortified antibiotics (tobramycin 1.5% + cefazolin 10%) for severe cases 1
• Add cycloplegic drops to decrease synechiae formation and reduce pain from anterior chamber inflammation 2

Limited Role for Erythromycin

Erythromycin ointment may only be considered:

• At bedtime as adjunctive therapy to fluoroquinolone drops in non-contact lens-related, uncomplicated abrasions 1
• Never as monotherapy in any contact lens wearer 1, 2

Evidence Quality

The 2024 American Academy of Ophthalmology Bacterial Keratitis Preferred Practice Pattern provides strong guideline evidence supporting mandatory antipseudomonal coverage with fluoroquinolones for all contact lens-related corneal abrasions. 1 While a 2025 Cochrane review found very low certainty evidence regarding the magnitude of benefit of prophylactic antibiotics, 5 the AAO maintains a strong recommendation due to the potentially devastating consequences of untreated Pseudomonas keratitis in contact lens wearers. 1

Critical Pitfalls to Avoid

• Do not use combination steroid-antibiotic preparations as initial therapy; steroids mask infection signs and worsen outcomes in fungal or Acanthamoeba keratitis. 1

• Do not use chronic prophylactic antibiotics beyond the acute treatment period, as this promotes resistant organisms. 1

• Methicillin-resistant Staphylococcus aureus (MRSA) accounts for approximately 42% of ocular isolates and frequently exhibits concurrent fluoroquinolone resistance, but fluoroquinolones remain first-line due to superior tissue penetration. 1