Treatment for Shingles (Herpes Zoster)
For immunocompetent adults with uncomplicated shingles, start oral valacyclovir 1 gram three times daily for 7-10 days, continuing until all lesions have completely scabbed. 1, 2
First-Line Oral Antiviral Options
The three FDA-approved oral antivirals are equally effective, but differ in dosing convenience:
Valacyclovir 1 gram three times daily is the preferred first-line option due to superior bioavailability and convenient dosing compared to acyclovir 1, 2
Famciclovir 500 mg three times daily offers equivalent efficacy to valacyclovir with the same dosing frequency 1, 3
Acyclovir 800 mg five times daily is effective but requires more frequent dosing, which reduces compliance and is therefore less preferred 4
Critical Timing and Duration
Initiate treatment within 48-72 hours of rash onset for maximum efficacy in reducing acute pain and preventing postherpetic neuralgia 1, 5
Continue treatment until all lesions have completely scabbed, not just for an arbitrary 7-day period—this is the key clinical endpoint 1, 4
Treatment initiated after 72 hours may still provide benefit for pain reduction, though earlier is better 6
When to Escalate to Intravenous Therapy
Switch to IV acyclovir 10 mg/kg every 8 hours for:
Disseminated herpes zoster (multi-dermatomal or visceral involvement) 1
Immunocompromised patients with severe disease or on active chemotherapy 1, 7
Complicated facial/ophthalmic zoster with suspected CNS involvement 1
Herpes zoster ophthalmicus requiring aggressive management 1
Continue IV therapy for minimum 7-10 days and until clinical resolution, with close monitoring of renal function 1
Special Population Considerations
Immunocompromised patients:
- Require IV acyclovir 10 mg/kg every 8 hours for severe cases 1
- Consider temporary reduction in immunosuppressive medications for disseminated disease 1, 4
- May need longer treatment duration until complete clinical resolution 7
HIV-positive patients:
- May require higher oral doses (up to 800 mg 5-6 times daily) 1
- Consider long-term prophylaxis with acyclovir 400 mg 2-3 times daily 1
Renal impairment:
- Mandatory dose adjustments required to prevent acute renal failure 1
- Monitor renal function closely during IV therapy 1
Pain Management
Initiate analgesics immediately alongside antivirals—achieving painlessness is a primary treatment goal 5
Combine appropriately dosed analgesics with neuroactive agents (e.g., amitriptyline) for neuropathic pain 5
Topical anesthetics provide minimal benefit and are not recommended as primary therapy 1
Adjunctive Corticosteroid Therapy
Prednisone may be considered as adjunctive therapy in select cases of severe, widespread shingles 1
Corticosteroids may shorten acute pain duration but have no essential effect on preventing postherpetic neuralgia 5
Avoid in immunocompromised patients due to increased risk of disseminated infection 1
Contraindicated in patients with poorly controlled diabetes, severe osteoporosis, or history of steroid-induced psychosis 1
Critical Pitfalls to Avoid
Never use topical acyclovir—it is substantially less effective than oral therapy 1, 4
Do not underdose: Acyclovir 400 mg three times daily is only appropriate for genital herpes, not shingles 1
Do not stop at 7 days if lesions haven't scabbed—continue until complete crusting occurs 1, 4
Do not delay treatment waiting for laboratory confirmation in typical presentations 5
Infection Control
- Patients are contagious until all lesions have crusted and should avoid contact with susceptible individuals (those who haven't had chickenpox), pregnant women, and immunocompromised persons 1, 7