Treatment of Shingles (Herpes Zoster)
For uncomplicated shingles, start oral valacyclovir 1 gram three times daily or famciclovir 500 mg three times daily for 7-10 days, continuing until all lesions have completely scabbed over. 1
First-Line Oral Antiviral Therapy
The cornerstone of shingles treatment is prompt initiation of oral antiviral therapy, ideally within 72 hours of rash onset (though treatment within 48 hours is optimal). 1, 2, 3
Standard dosing regimens:
- Valacyclovir 1 gram three times daily for 7 days 2
- Famciclovir 500 mg three times daily for 7 days 3
- Acyclovir 800 mg five times daily for 7-10 days 1
Valacyclovir and famciclovir offer superior bioavailability and more convenient dosing schedules compared to acyclovir, which requires five daily doses versus three. 1, 4 The key clinical endpoint is complete scabbing of all lesions, not an arbitrary 7-day duration—continue treatment if lesions remain active beyond 7 days. 1
When to Escalate to Intravenous Therapy
Intravenous acyclovir is mandatory for:
- Disseminated or invasive herpes zoster (multi-dermatomal or visceral involvement) 1
- Immunocompromised patients with severe disease 1, 5
- Complicated facial zoster with suspected CNS involvement 1
- Severe ophthalmic disease 1
IV acyclovir dosing: 5-10 mg/kg every 8 hours until clinical resolution 6, 5. For severely immunocompromised hosts (e.g., patients on chemotherapy, HIV-infected with low CD4 counts), use 10 mg/kg every 8 hours. 1 Monitor renal function closely and adjust doses for renal impairment. 1
Special Populations
Immunocompromised patients:
- Consider temporary reduction in immunosuppressive medications for disseminated disease 1
- May require extended treatment duration well beyond 7-10 days as lesions continue to develop over 7-14 days and heal more slowly 1
- High-dose IV acyclovir remains the treatment of choice for severely compromised hosts 1
Facial/ophthalmic involvement:
- Requires particular urgency due to risk of cranial nerve complications and vision loss 1
- Consider IV therapy for complicated cases 1
- Ophthalmology referral is warranted for ocular involvement 7
Critical Treatment Principles
Timing matters: Treatment is most effective when initiated within 48 hours of rash onset, but the 72-hour window is the maximum timeframe for optimal efficacy. 1 However, treatment initiated beyond 72 hours may still provide benefit for pain reduction. 8
Avoid topical antivirals: Topical acyclovir is substantially less effective than systemic therapy and should not be used. 1
Continue until complete healing: The treatment endpoint is complete scabbing of all lesions, not calendar days. 1 Immunocompromised patients may develop chronic ulcerations without adequate antiviral therapy. 1
Infection Control
Patients must avoid contact with susceptible individuals (those who have not had chickenpox or vaccination) until all lesions have crusted over, as lesions are contagious. 6, 5
Adjunctive Pain Management
While antivirals address viral replication, appropriately dosed analgesics combined with neuroactive agents (such as amitriptyline) are essential for pain control during acute infection. 9 Corticosteroids may provide modest benefits for acute pain but do not significantly prevent postherpetic neuralgia and carry risks, particularly in elderly patients. 1
Prevention
The recombinant zoster vaccine (Shingrix) is recommended for all adults aged 50 years and older, regardless of prior herpes zoster episodes, and ideally should be given before initiating immunosuppressive therapies. 1