What is the treatment for herpetic keratitis (cold sore eye infection)?

Treatment of Herpetic Keratitis (Cold Sore Eye Infection)

For herpetic keratitis, a combination of topical antiviral agents (preferably ganciclovir 0.15% gel) and oral antiviral therapy is the most effective treatment approach. 1

First-Line Treatment Options

Topical Antiviral Options:

• Ganciclovir 0.15% gel three to five times daily (preferred due to FDA approval for acute herpetic keratitis and better ocular surface tolerability) 1, 2
• Trifluridine 1% solution five to eight times daily (effective but causes epithelial toxicity if used longer than 2 weeks) 3, 1

Oral Antiviral Options:

• Acyclovir 200-400 mg five times daily 3, 1
• Valacyclovir 500 mg two to three times daily (better bioavailability than acyclovir) 3, 1
• Famciclovir 250 mg twice daily 3, 1

Treatment Algorithm Based on Type of Herpetic Keratitis

Epithelial Herpetic Keratitis (Dendritic/Geographic Ulcers):

• Start with topical ganciclovir 0.15% gel 3-5 times daily 1, 2
• Add oral antiviral therapy in moderate to severe cases 1
• Follow-up within 1 week to assess healing 1

Stromal Keratitis:

• Combination of oral antiviral therapy and topical corticosteroids at minimum effective dose 1
• Oral antivirals are essential when using topical steroids to prevent viral replication 3, 1
• Topical steroids should be tapered slowly once inflammation is controlled 3
• Use corticosteroids with poor ocular penetration (fluorometholone, loteprednol) to minimize IOP elevation and cataract formation 3, 1

Endotheliitis (Disciform Keratitis):

• Combination of oral antiviral therapy and topical corticosteroids 1, 4
• Monitor IOP regularly due to risk of secondary glaucoma 1

Neurotrophic Keratopathy (Metaherpetic Keratitis):

• Intensive lubrication 4
• Consider bandage contact lens or amniotic membrane in persistent epithelial defects 1
• Continue oral antivirals to prevent recurrence 4

Duration of Treatment and Monitoring

• Initial treatment should continue until complete re-epithelialization occurs 1
• Follow-up within 1 week of initiating treatment to assess:
  • Reduced pain and discharge 1
  • Decreased corneal infiltrate density 1
  • Initial re-epithelialization 1
  • Cessation of progressive corneal thinning 1
• For patients using topical corticosteroids, regular monitoring of IOP and pupillary dilation is essential 3, 1

Prevention of Recurrence

• Long-term prophylaxis with oral antivirals at lower doses may be considered for patients with frequent recurrences 3, 5
• After keratoplasty and in cases of severe recurrences, systemic acyclovir (2×400 mg/day) for at least 1 year is recommended 4
• Topical artificial tears (with acyclovir ointment at night if needed) during quiet intervals may limit recurrences 4

Important Pitfalls to Avoid

• Never use topical corticosteroids without antiviral coverage in epithelial HSV keratitis as this can potentiate the infection 3, 1
• Avoid prolonged use of trifluridine beyond 2 weeks due to epithelial toxicity 3, 1
• Don't confuse medication toxicity with worsening infection 1
• Be aware that recurrent episodes can lead to structural damage of the cornea and may eventually require corneal transplantation 6, 5
• Avoid prostaglandin analogues when treating concomitant ocular hypertension 4