Treatment of Shingles (Herpes Zoster)
Start oral antiviral therapy immediately—ideally within 72 hours of rash onset—with valacyclovir 1000 mg three times daily, famciclovir 500 mg three times daily, or acyclovir 800 mg five times daily for 7 days in immunocompetent patients. 1, 2, 3
Antiviral Therapy Selection
The three FDA-approved oral antivirals are equally effective for treating shingles, but differ in dosing convenience:
- Valacyclovir 1000 mg three times daily for 7 days is the standard regimen, offering superior pain control compared to acyclovir and equivalent efficacy to famciclovir 1, 4
- Famciclovir 500 mg three times daily for 7 days demonstrates comparable efficacy to valacyclovir for lesion healing and pain reduction 2, 4
- Acyclovir 800 mg five times daily for 7 days is effective but requires more frequent dosing, which may reduce compliance 3, 4
The primary goal is to accelerate rash healing, reduce acute pain, and prevent postherpetic neuralgia—the most debilitating complication. 5, 3
Timing of Treatment
- Initiate therapy within 72 hours of rash onset for maximum benefit in reducing acute symptoms and preventing postherpetic neuralgia 5, 3
- Treatment started beyond 72 hours may still provide benefit for pain control, though evidence is less robust 4
- Begin treatment immediately upon clinical diagnosis without waiting for laboratory confirmation 3
Special Populations Requiring Aggressive Treatment
Immunocompromised patients with severe disease require intravenous acyclovir 5-10 mg/kg every 8 hours until clinical resolution, with potentially prolonged treatment duration 6, 7
High-Risk Groups Requiring Urgent Antiviral Therapy:
- All patients ≥50 years of age (highest risk for postherpetic neuralgia) 3, 8
- Herpes zoster involving the head and neck, particularly zoster ophthalmicus (risk of vision-threatening complications) 3
- Immunosuppressed patients (HIV, chemotherapy, chronic corticosteroids, malignancies) 5, 3
- Severe disease on trunk or extremities regardless of age 3
- Patients with severe atopic dermatitis or eczema 3
Pain Management
Combine antivirals with adequate analgesia from the outset, as pain control is the most critical treatment outcome 3:
- Start with appropriately dosed analgesics (including opioids if necessary for severe pain) 5, 3
- Add a neuroactive agent such as amitriptyline early in the course 3
- Consider tricyclic antidepressants or anticonvulsants in low doses for neuropathic pain control 5
- Topical options include capsaicin or lidocaine patches for selected patients 5
Corticosteroid Consideration
Corticosteroids may provide modest benefit in reducing acute zoster pain but do not significantly prevent postherpetic neuralgia 5, 3. Their use should be adjunctive to antivirals, not a substitute.
Common Pitfalls to Avoid
- Delaying treatment beyond 72 hours due to diagnostic uncertainty—treat based on clinical presentation 3
- Underprescribing antivirals in high-risk patients (50% of elderly patients in community studies received suboptimal treatment) 8
- Inadequate pain control during acute phase, which correlates with development of postherpetic neuralgia 8
- Failing to refer zoster ophthalmicus to ophthalmology, as ocular complications can be vision-threatening 5
Patient Education
Counsel patients that lesions remain contagious to individuals who have not had chickenpox until all lesions are fully crusted 6, 7. Patients should avoid contact with susceptible individuals (pregnant women, immunocompromised persons, infants) during this period.
Adverse Effects
Antivirals are generally well-tolerated, with the most common side effects being nausea, headache, and gastrointestinal disturbances 6, 4. These rarely require treatment discontinuation.