What is the recommended treatment for herpes zoster?

Treatment of Herpes Zoster

For uncomplicated herpes zoster, initiate oral valacyclovir 1 gram three times daily for 7 days, starting within 72 hours of rash onset. 1

First-Line Antiviral Therapy

Valacyclovir 1 gram orally three times daily for 7 days is the recommended first-line treatment for uncomplicated herpes zoster. 1 This regimen should be initiated as soon as possible, ideally within 72 hours of rash onset, though treatment beyond this window may still provide benefit in certain populations. 1

Alternative Oral Antiviral Options

If valacyclovir is unavailable or not tolerated, acceptable alternatives include:

• Acyclovir 800 mg orally five times daily for 7 days 1
• Famciclovir 500 mg every 8 hours for 7 days 1, 2

Both famciclovir and valacyclovir offer more favorable dosing schedules than acyclovir's five-times-daily regimen, which may enhance patient compliance. 1 All three agents demonstrate similar efficacy in reducing acute pain duration and accelerating cutaneous healing. 3

Treatment Based on Disease Severity

Uncomplicated Herpes Zoster

• Start oral valacyclovir 1 gram three times daily for 7 days 1
• Treatment should continue for a minimum of 7-10 days 1
• Continue treatment until clinical resolution if new lesions persist beyond 7 days 1

Severe or Disseminated Disease

For disseminated, multi-dermatomal, ophthalmic, visceral, or complicated herpes zoster, switch to intravenous acyclovir 5-10 mg/kg every 8 hours. 1 This includes:

• Patients requiring hospitalization due to severe disease 1
• Evidence of cutaneous or visceral dissemination 1
• Central nervous system involvement 1
• Herpes zoster ophthalmicus (requires urgent treatment) 1

Continue IV therapy until clinical improvement occurs, then switch to oral therapy to complete the treatment course. 1 The minimum treatment duration is 7-10 days, but therapy should continue until clinical resolution is attained. 1

Special Populations Requiring Urgent Treatment

Immunocompromised Patients

• All immunocompromised patients with herpes zoster require antiviral treatment regardless of timing from rash onset 1
• Consider longer treatment duration if healing is delayed 1
• Monitor closely for dissemination and visceral complications 1
• Temporarily reduce or discontinue immunosuppressive therapy in severe cases of disseminated VZV infection 1
• Immunosuppression may be restarted after commencing anti-VZV therapy and after skin vesicles have resolved 1

High-Risk Immunocompetent Patients Requiring Treatment

• Patients ≥50 years of age (at increased risk for postherpetic neuralgia) 1
• Herpes zoster in the head and neck area, especially zoster ophthalmicus 1
• Severe herpes zoster on the trunk or extremities 1
• Patients with severe atopic dermatitis or severe eczema 4

Ramsay Hunt Syndrome (Herpes Zoster Oticus)

For herpes zoster affecting the ear with facial nerve involvement, initiate valacyclovir 1 gram three times daily for 7 days PLUS systemic corticosteroids within 72 hours of symptom onset. 5 This condition presents with vesicles on the external ear canal and posterior auricle, severe otalgia, facial paralysis, loss of taste on the anterior two-thirds of the tongue, and decreased lacrimation. 5

Acyclovir-Resistant Cases

For suspected acyclovir-resistant herpes zoster, switch to foscarnet 40 mg/kg IV every 8 hours. 1 Acyclovir-resistant isolates are routinely resistant to ganciclovir as well. 1 This scenario is most likely in severely immunocompromised patients with prolonged antiviral exposure. 1

Dosing Adjustments for Renal Impairment

For patients with creatinine clearance <60 mL/min, dose adjustments are required:

Famciclovir dosing in renal impairment for herpes zoster: 2

• CrCl ≥60: 500 mg every 8 hours
• CrCl 40-59: 500 mg every 12 hours
• CrCl 20-39: 500 mg every 24 hours
• CrCl <20: 250 mg every 24 hours
• Hemodialysis: 250 mg following each dialysis

Similar adjustments apply to valacyclovir and acyclovir based on renal function. 1

Critical Pitfalls to Avoid

• Do not delay treatment waiting for laboratory confirmation - diagnosis is clinical and treatment should begin immediately 5
• Do not rely on topical antivirals - systemic therapy is mandatory 5
• Do not withhold treatment in immunocompromised patients even if >72 hours from rash onset - they require treatment regardless of timing 1
• Do not confuse Ramsay Hunt syndrome with acute otitis externa - look for vesicles, facial paralysis, and severe pain 5
• Delayed initiation beyond 72 hours may reduce effectiveness in immunocompetent patients, though treatment may still be beneficial 1

Pain Management Considerations

Appropriately dosed analgesics in combination with neuroactive agents (such as amitriptyline) should be given together with antiviral therapy to achieve painlessness. 4 For postherpetic neuralgia, consider tricyclic antidepressants, gabapentin, pregabalin, topical lidocaine, or capsaicin. 6