What is the first‑line topical antibiotic eye drop for an uncomplicated corneal abrasion in a contact‑lens wearer without fluoroquinolone allergy?

First-Line Topical Antibiotic for Contact Lens-Related Corneal Abrasion

For an uncomplicated corneal abrasion in a contact lens wearer without fluoroquinolone allergy, prescribe a fourth-generation fluoroquinolone eye drop—specifically moxifloxacin 0.5% or gatifloxacin 0.5%—applied four times daily until complete epithelial healing is confirmed. 1, 2

Why Fluoroquinolones Are Mandatory in Contact Lens Wearers

• Contact lens-related abrasions require mandatory antipseudomonal coverage because contact lens wear dramatically increases the risk of Pseudomonas aeruginosa keratitis, a vision-threatening infection. 1, 3
• Fourth-generation fluoroquinolones (moxifloxacin, gatifloxacin) provide superior corneal tissue penetration and broad-spectrum coverage against both gram-positive and gram-negative organisms, including Pseudomonas. 1, 2
• These agents have demonstrated at least equivalent efficacy to fortified combination antibiotic therapy (tobramycin + cefazolin) in bacterial keratitis. 1

Specific Dosing and Duration

• Moxifloxacin 0.5%: one drop to the affected eye four times daily until epithelial healing is documented on examination. 1, 2
• Alternative: Gatifloxacin 0.5% or levofloxacin 1.5% using the same four-times-daily regimen. 1, 2
• Treatment must be initiated within 24 hours of injury for maximum effectiveness in preventing bacterial ulceration. 1, 3

Critical Management Principles for Contact Lens Wearers

• Never patch the eye in contact lens wearers—patching does not improve pain, may delay healing, and significantly increases bacterial keratitis risk. 1, 2
• Advise complete discontinuation of contact lens wear until healing is confirmed by examination. 1, 2
• Do not place a therapeutic bandage contact lens on contact lens-related abrasions, as this elevates secondary bacterial keratitis risk. 3

Adjunctive Measures

• Consider adding antibiotic ointment at bedtime for additional lubrication and overnight protection. 1
• Use over-the-counter oral acetaminophen or NSAIDs for pain control—avoid topical anesthetics beyond the initial examination. 1, 2

Mandatory Follow-Up and Red Flags

• All contact lens wearers require re-evaluation within 24 hours to assess healing and detect early infection. 1
• Obtain emergent ophthalmology consultation if any of the following develop: 1
  • Central infiltrate >2 mm
  • Significant stromal involvement or corneal melting
  • Corneal infiltrate with suppuration, necrosis, or feathery margins
  • Increasing pain, purulent discharge, or vision changes despite treatment

Important Caveats and Pitfalls

• Avoid combination steroid-antibiotic drops as initial therapy—steroids delay healing and increase infection risk. 1, 2
• Steroids should only be added after 2–3 days of antibiotic-only therapy if bacterial infection is controlled. 1
• Never use corticosteroids in suspected Acanthamoeba, Nocardia, or fungal infections—they worsen outcomes. 1
• Chronic prophylactic antibiotic use promotes resistant organisms; use antibiotics only for the finite healing period. 1, 2
• Increasing resistance of MRSA and Pseudomonas to fluoroquinolones has been documented, but fluoroquinolones remain first-line due to superior tissue penetration and clinical efficacy. 1, 3

Why Not Tetracycline Ointment?

• Ocular ointments, including tetracycline, lack adequate solubility and cannot penetrate the cornea significantly for optimal therapeutic benefit. 3
• Tetracycline ointment may be useful at bedtime as adjunctive therapy to fluoroquinolone drops in less severe cases, but should never be used as monotherapy. 3
• Topical antibiotic drops are preferred over ointments because drops achieve higher tissue levels in the cornea. 2

Evidence Quality

• The 2024 American Academy of Ophthalmology Bacterial Keratitis Preferred Practice Pattern provides strong guideline evidence supporting topical antibiotics for corneal abrasion prophylaxis, particularly in contact lens wearers. 4, 1
• A 2022 Cochrane systematic review reported very low certainty evidence regarding the magnitude of benefit of prophylactic antibiotics in preventing infection, but the AAO recommends prophylactic antibiotics because of the potentially severe consequences of untreated bacterial keratitis in high-risk populations. 5