Treatment of Herpes Zoster (Shingles)
For uncomplicated herpes zoster, start oral valacyclovir 1 gram three times daily for 7 days, ideally within 72 hours of rash onset. 1
First-Line Antiviral Treatment for Uncomplicated Cases
- Valacyclovir 1 gram orally three times daily for 7 days is the preferred first-line treatment for uncomplicated herpes zoster 1
- Acyclovir 800 mg orally five times daily for 7 days is an acceptable alternative, though the dosing schedule is less convenient 1, 2
- Famciclovir offers better bioavailability and less frequent dosing compared to acyclovir, improving adherence 3
- Treatment must be initiated within 72 hours of rash onset for maximum effectiveness; delayed initiation significantly reduces efficacy 1, 2
- Continue treatment until all lesions have scabbed, which typically takes 7-10 days 1, 3
The evidence strongly supports valacyclovir as first-line due to superior dosing convenience (three times daily versus five times daily for acyclovir), which improves patient adherence without compromising efficacy.
Treatment for Severe or Disseminated Disease
- Intravenous acyclovir 5-10 mg/kg every 8 hours is required for disseminated or invasive herpes zoster 1, 4
- Continue IV therapy until clinical improvement occurs, then switch to oral therapy to complete the treatment course 1
- Temporarily reduce immunosuppressive medications if the patient is on such therapy 1, 3
- Treatment should continue until clinical resolution is attained, which may extend beyond 7 days if new lesions continue to form or healing is incomplete 1
Severe disease includes cutaneous dissemination beyond the primary dermatome, visceral involvement (pneumonitis, hepatitis, encephalitis), or involvement in severely immunocompromised hosts 4, 5.
Special Populations and Considerations
Immunocompromised Patients
- Monitor closely for dissemination and complications as these patients are at 15-fold higher risk than immunocompetent individuals 4, 1
- Consider longer treatment duration if healing is delayed 1
- High-dose IV acyclovir remains the treatment of choice for severely compromised hosts 3
- Chronic ulcerations with persistent viral replication and secondary bacterial/fungal superinfections can occur 6
Acyclovir-Resistant Cases
- Foscarnet 40 mg/kg IV every 8 hours may be required for suspected acyclovir-resistant herpes zoster 1
- Acyclovir-resistant isolates are routinely resistant to ganciclovir as well 4
Ophthalmic Involvement
- Ophthalmic herpes zoster can lead to serious complications including keratitis, iridocyclitis, secondary glaucoma, and vision loss 2, 7
- These cases generally merit referral to an ophthalmologist 2
Post-Exposure Prophylaxis
- Varicella-zoster immunoglobulin within 96 hours of exposure is recommended for varicella-susceptible patients exposed to active infection 1, 3
- If immunoglobulin is unavailable or >96 hours have passed, give oral acyclovir for 7 days beginning 7-10 days after exposure 1, 3
Critical Pitfalls to Avoid
- Do not use topical antiviral therapy as it is substantially less effective than systemic therapy 3
- Do not delay treatment beyond 72 hours of rash onset, as this significantly reduces effectiveness 1
- Do not discontinue treatment prematurely if new lesions continue to form or healing is incomplete 1
- In immunocompromised patients, do not use oral therapy alone for severe disease—IV acyclovir is required 3
Pain Management Considerations
- Acute neuritis and postherpetic neuralgia may require analgesics, including tricyclic antidepressants (amitriptyline) or anticonvulsants in low dosages 2, 7
- Capsaicin, lidocaine patches, and nerve blocks can be used in selected patients with postherpetic neuralgia 2
- Corticosteroids (prednisone) may provide modest benefits in reducing acute pain and incidence of postherpetic neuralgia when used as adjunctive therapy to antivirals, but should generally be avoided in immunocompromised patients due to increased risk of disseminated infection 3, 2