What is the treatment for herpes zoster ophthalmicus?

Treatment of Herpes Zoster Ophthalmicus

The treatment of herpes zoster ophthalmicus requires prompt administration of oral antiviral medications within 72 hours of rash onset, with valacyclovir 1000mg three times daily for 7 days being the preferred regimen due to its superior bioavailability compared to acyclovir. 1, 2

Systemic Antiviral Therapy

Systemic antiviral medications are the cornerstone of treatment for herpes zoster ophthalmicus. Options include:

• Valacyclovir: 1000mg three times daily for 7 days
• Acyclovir: 800mg five times daily for 7 days
• Famciclovir: 500mg three times daily for 7 days

While the Cochrane review found uncertainty regarding the superiority of valacyclovir over acyclovir due to limited evidence 3, valacyclovir offers better bioavailability and a more convenient dosing schedule, which may improve compliance.

Topical Therapy

• Topical antivirals alone are not effective for treating VZV conjunctivitis but may be used as adjunctive therapy in unresponsive cases 4
• Topical antibiotics may be prescribed to prevent secondary bacterial infection of vesicular lesions 4
• Caution: Topical corticosteroids should be avoided during active epithelial disease as they can potentiate viral infection 4

Management Algorithm

1. Initial Presentation:

   • Begin oral antiviral therapy within 72 hours of rash onset
   • Consider topical antibiotics if eyelid ulceration is present

2. Ocular Involvement Assessment:

   • Evaluate for conjunctivitis, keratitis, uveitis, and cranial nerve palsies
   • Refer to ophthalmologist if any ocular involvement is present 2

3. Follow-up:

   • Re-evaluate within 1 week of treatment initiation
   • Assessment should include interval history, visual acuity measurement, and slit-lamp biomicroscopy 4

4. Management of Complications:

   • For stromal keratitis or uveitis: Consider topical corticosteroids only in conjunction with systemic antiviral coverage 4
   • For persistent ocular inflammation: Taper topical corticosteroids to minimum effective dose 4
   • For neurotrophic keratitis: Manage dry eye and corneal anesthesia 4

Special Considerations

• Immunocompromised patients may require more aggressive treatment and longer duration of therapy 4
• Patients with renal impairment need dose adjustment of antiviral medications 4
• Chronic sequelae may require prolonged treatment or long-term prophylaxis 4

Potential Complications

• Permanent sequelae may include chronic ocular inflammation, vision loss, and debilitating post-herpetic neuralgia 2
• Late sequelae include dry eye syndrome and corneal anesthesia with neurotrophic keratitis 4
• Severe conjunctival scarring from secondary bacterial infection can lead to cicatricial ectropion 4

Monitoring

• Monitor for signs of corneal involvement, including pseudodendrites, keratitis, and corneal scarring
• Watch for development of uveitis, sectoral iris atrophy, and secondary glaucoma 4
• For patients on topical corticosteroids, regularly measure IOP and assess for cataract formation 4

Early treatment with oral antivirals has been shown to reduce the severity of skin eruption, decrease the incidence and severity of ocular complications, and potentially reduce the intensity of post-herpetic neuralgia 5, 6.