What is the best treatment approach for a patient with herpes zoster ophthalmicus (shingles eye)?

Treatment of Herpes Zoster Ophthalmicus (Shingles Eye)

Initiate oral antiviral therapy immediately—ideally within 72 hours of rash onset—with valacyclovir 1000 mg three times daily for 7 days, famciclovir 500 mg three times daily for 7 days, or acyclovir 800 mg five times daily for 7 days, and arrange urgent ophthalmology consultation within 24 hours. 1

Immediate Antiviral Management

Valacyclovir is the preferred first-line agent due to superior bioavailability and less frequent dosing (three times daily versus five times daily for acyclovir), which significantly improves patient adherence. 1 Alternative regimens include:

• Valacyclovir 1000 mg three times daily for 7 days (preferred) 1
• Famciclovir 500 mg three times daily for 7 days 1
• Acyclovir 800 mg five times daily for 7 days 1, 2

The 72-hour window is critical—antiviral therapy started within this timeframe reduces acute pain severity, accelerates lesion healing, prevents dissemination (which occurs in 10-20% without treatment), and dramatically decreases late ocular complications from 50-71% down to 29%. 1, 2 Research confirms that 7 days of treatment is sufficient; extending to 14 days provides no additional benefit in immunocompetent patients. 2

Do not stop treatment at exactly 7 days if new lesions are still forming or existing lesions have not completely scabbed—the clinical endpoint is complete crusting of all lesions, not an arbitrary calendar duration. 1

Urgent Ophthalmology Referral

Any involvement of the forehead, eyelid, or nose (Hutchinson's sign) mandates ophthalmology evaluation within 24 hours, as this indicates nasociliary nerve involvement and predicts a 76% risk of ocular complications. 1, 3 Daily ophthalmologic review is necessary during the acute illness phase. 1

Ocular Supportive Care

Apply non-preserved ocular lubricants (hyaluronate or carmellose drops) every 2 hours throughout the acute illness to prevent corneal exposure damage. 1 Perform daily ocular hygiene by an ophthalmologist or ophthalmically-trained nurse. 1

If corneal fluorescein staining or ulceration is present, administer broad-spectrum topical antibiotics (moxifloxacin drops four times daily) to prevent secondary bacterial infection. 1

Topical Corticosteroid Use: Critical Caveats

Never use topical corticosteroids without concurrent systemic antiviral therapy—steroids potentiate viral replication and can cause devastating worsening of disease. 1

When stromal keratitis or uveitis develops (typically 1-2 weeks after rash onset), topical corticosteroids become necessary but must follow strict protocols:

• Use corticosteroids with poor ocular penetration (fluorometholone, rimexolone, or loteprednol) to minimize intraocular pressure elevation and cataract formation 1
• Consider non-preserved dexamethasone 0.1% twice daily only under ophthalmologic supervision 1
• Taper slowly to the minimum effective dose to prevent rebound inflammation 1
• Avoid topical trifluridine for more than 2 weeks as it inevitably causes epithelial toxicity 1

Escalation to Intravenous Therapy

Switch to intravenous acyclovir 10 mg/kg every 8 hours for: 4, 1

• Immunocompromised patients (HIV, chemotherapy, chronic corticosteroids, transplant recipients)
• Disseminated disease (lesions beyond the primary dermatome)
• Suspected CNS involvement (altered mental status, severe headache)
• Inability to tolerate oral medications
• Failure to respond to oral therapy within 7-10 days

High-dose IV acyclovir remains the treatment of choice for VZV infections in compromised hosts, as oral therapy should be reserved only for mild cases with transient immunosuppression. 4

Monitoring and Dose Adjustments

Monitor renal function in elderly patients or those with baseline renal impairment, as acyclovir and valacyclovir require dose adjustment based on creatinine clearance. 1 Inadequate dose reduction can cause acyclovir-induced nephrotoxicity or neurotoxicity.

If lesions fail to improve within 7-10 days despite appropriate therapy, suspect acyclovir resistance (particularly in patients already taking prophylactic antivirals for transplant), obtain viral culture with susceptibility testing, and switch to foscarnet 40 mg/kg IV every 8 hours. 4, 1

Prevention of Future Episodes

Administer the recombinant zoster vaccine (Shingrix) once acute symptoms resolve—typically waiting at least 2 months after the episode. 1 Shingrix provides 96-97% efficacy in preventing future episodes compared to 70% for the older live vaccine, and is recommended for all adults aged 50 years and older regardless of prior herpes zoster history. 1 The two-dose series should be given 2-6 months apart. 1

Common Pitfalls to Avoid

• Do not delay treatment waiting for ophthalmology consultation—start oral antivirals immediately and arrange urgent referral 1
• Do not use corticosteroids alone without systemic antivirals 1
• Do not assume 7 days is always sufficient—continue until complete crusting occurs 1
• Do not forget renal dose adjustments in elderly or renally impaired patients 1
• Do not overlook immunocompromised status—these patients require IV therapy from the outset 4