Treatment of Shingles (Herpes Zoster)
For uncomplicated shingles in immunocompetent adults, initiate oral antiviral therapy with valacyclovir, famciclovir, or acyclovir within 72 hours of rash onset and continue treatment until all lesions have completely scabbed. 1
First-Line Antiviral Options
The three FDA-approved oral antivirals are equally effective, but differ in dosing convenience:
- Valacyclovir 1 gram three times daily for 7 days is a preferred option due to better bioavailability and convenient dosing 1, 2
- Famciclovir 500 mg every 8 hours for 7 days offers similar efficacy with three-times-daily dosing 3, 4
- Acyclovir 800 mg five times daily for 7-10 days is effective but requires more frequent dosing, which may reduce compliance 1, 5, 2
Treatment should be initiated within 72 hours of rash onset for maximum benefit, though starting within 48 hours is optimal 1. These antivirals shorten viral shedding, accelerate rash healing by 1-2 days, and reduce the intensity and duration of acute pain 4, 2.
Critical Treatment Endpoint
Continue antiviral therapy until all lesions have completely scabbed—this is the key clinical endpoint, not an arbitrary 7-day duration. 1 If lesions remain active beyond 7 days, extend treatment accordingly 1.
When to Escalate to Intravenous Therapy
Intravenous acyclovir is required for:
- Disseminated herpes zoster (multi-dermatomal involvement or visceral disease) 1
- Immunocompromised patients with severe disease, including those on chemotherapy, high-dose steroids, or with HIV 1
- Facial zoster with suspected CNS involvement or severe ophthalmic complications 1
For these patients, use IV acyclovir 5-10 mg/kg every 8 hours and consider temporarily reducing immunosuppressive medications 1, 5.
Special Populations
Immunocompromised Patients
- Require more aggressive management with consideration for IV therapy even with localized disease 1
- Monitor closely for dissemination and treatment failure 1
- Consider acyclovir prophylaxis for patients on proteasome inhibitors (e.g., bortezomib) at 400 mg daily 1
Renal Impairment
- Mandatory dose adjustments based on creatinine clearance to prevent acute renal failure 1, 3
- Monitor renal function closely during IV acyclovir therapy 1
HIV-Infected Patients
- May require higher oral doses (up to 800 mg 5-6 times daily) or longer treatment courses 1
- Consider long-term prophylaxis (400 mg 2-3 times daily) for recurrent episodes 1
Adjunctive Corticosteroid Therapy
Corticosteroids are NOT routinely recommended. While prednisone may provide modest benefit for acute pain reduction during the first 7-14 days, it offers no reduction in postherpetic neuralgia and carries significant risks, particularly in elderly patients 6. The American Academy of Dermatology suggests prednisone may be considered only in select cases of severe, widespread disease as adjunctive therapy to antivirals 1.
Avoid corticosteroids in immunocompromised patients due to increased risk of disseminated infection 1.
Critical Pitfalls to Avoid
- Never use topical acyclovir—it is substantially less effective than oral therapy and is not recommended 1, 5
- Do not underdose or use inadequate treatment duration, as this increases treatment failure and complication risk 5
- Do not stop treatment at 7 days if lesions have not fully scabbed—continue until complete crusting occurs 1
- Monitor for acyclovir resistance if lesions persist despite adequate therapy; consider foscarnet for resistant cases 1
Infection Control
- Patients remain contagious until all lesions have crusted and should avoid contact with susceptible individuals (pregnant women, immunocompromised persons, those without varicella immunity) 1