What is the recommended management of herpes zoster ophthalmicus, including first‑line oral antiviral therapy, urgent ophthalmology referral, and indications for intravenous antiviral treatment or dose adjustment in renal impairment?

Management of Herpes Zoster Ophthalmicus

Start oral valacyclovir 1000 mg three times daily for 7 days immediately upon diagnosis, ideally within 72 hours of rash onset, and arrange urgent ophthalmology referral within 1 week. 1

First-Line Oral Antiviral Therapy

Valacyclovir is the preferred first-line agent for immunocompetent adults with herpes zoster ophthalmicus at 1000 mg three times daily for 7 days. 1, 2 This regimen offers superior convenience compared to alternatives while maintaining equivalent efficacy.

Alternative oral regimens include:

• Acyclovir 800 mg five times daily for 7 days 1, 2
• Famciclovir 500 mg three times daily for 7 days 1, 2

Treatment duration must be a minimum of 7-10 days, with potential extension for chronic or recalcitrant disease requiring dose adjustments based on clinical response. 1, 2

Timing is critical: Antiviral therapy is most effective when initiated within 72 hours of rash onset to prevent ocular complications. 3, 4 However, treatment should still be started even if this window has passed, as late initiation may still provide benefit. 5

Renal Dose Adjustment

Exercise caution in patients with impaired renal clearance and adjust antiviral doses accordingly to prevent nephrotoxicity. 6, 2 Valacyclovir and acyclovir require dose reduction based on creatinine clearance, though specific adjustments should follow standard renal dosing protocols.

Indications for Intravenous Antiviral Therapy

Switch to intravenous acyclovir for:

• Complicated herpes zoster ophthalmicus with severe ocular involvement 1
• Signs of cutaneous or visceral dissemination 5
• Immunocompromised patients requiring more aggressive therapy 1, 2

Note that in immunocompetent patients, even optic nerve involvement may respond to oral valacyclovir, making hospitalization for IV therapy potentially unnecessary in select cases. 7

Adjunctive Topical Management

Apply topical antibiotics to vesicular lesions to prevent secondary bacterial infection, which can cause severe conjunctival scarring and cicatricial ectropion. 1, 2

Do not use topical antivirals as monotherapy—they are ineffective for varicella-zoster virus conjunctivitis and should only be considered as additive treatment in unresponsive patients already on systemic therapy. 6, 1, 2

Critical Corticosteroid Precautions

Topical corticosteroids are absolutely contraindicated during active epithelial viral infection because they potentiate viral replication and worsen disease. 1, 2

Corticosteroids may only be used after epithelial healing for inflammatory complications such as stromal keratitis or uveitis, and only under direct ophthalmologist supervision. 1, 2 When indicated:

• Use the minimum effective dose 1
• Prefer agents with poor ocular penetration (fluorometholone or loteprednol) to minimize intraocular pressure elevation and cataract risk 1
• Taper slowly 1

Urgent Ophthalmology Referral

Arrange ophthalmology evaluation within 1 week of treatment initiation for all patients with herpes zoster ophthalmicus. 1, 2 This visit must include:

• Interval history focusing on pain, visual changes, and new ocular symptoms 1
• Visual acuity measurement 1, 2
• Slit-lamp biomicroscopy to detect early complications 1, 2

Immediate ophthalmology referral is warranted when ocular involvement is clinically evident at presentation to limit visual morbidity. 4

Ongoing Monitoring

For patients on corticosteroid therapy:

• Measure intraocular pressure regularly to identify steroid-induced glaucoma early 1, 2
• Perform pupillary dilation to evaluate for cataract formation 2
• Monitor for recurrence of sub-epithelial infiltrates, which typically appear one or more weeks after disease onset 1

Surveillance for specific ocular complications should include watching for sectoral iris atrophy, secondary glaucoma, corneal scarring, pseudodendrites, keratitis, corneal vascularization, and uveitis. 6, 1, 2

Late sequelae may include dry eye and corneal anesthesia with neurotrophic keratitis, requiring ongoing monitoring. 6, 2

Special Populations

Immunocompromised patients require more aggressive antiviral therapy with potential dose adjustments based on clinical response. 1, 2 In severe cases of disseminated VZV, consider discontinuing immunosuppressive therapy temporarily; it may be restarted after commencing anti-VZV therapy and resolution of skin vesicles. 1

Common Pitfalls to Avoid

• Do not delay treatment waiting for ophthalmology consultation—start oral antivirals immediately upon diagnosis 1, 4
• Do not use topical corticosteroids empirically—they worsen active infection and should only be used for specific inflammatory complications after epithelial healing under specialist guidance 1, 2
• Do not rely on topical antivirals alone—they are ineffective as monotherapy 1, 2
• Do not forget renal dosing adjustments—failure to adjust can lead to nephrotoxicity 2