Treatment of Shingles Rash
Oral antiviral therapy with valacyclovir 1000 mg three times daily for 7 days, acyclovir 800 mg five times daily for 7-10 days, or famciclovir 500 mg three times daily for 7 days should be initiated as soon as possible—ideally within 72 hours of rash onset—to reduce viral replication, accelerate healing, and decrease the severity and duration of acute pain. 1, 2, 3, 4
First-Line Antiviral Options
The three FDA-approved oral antivirals for herpes zoster are equally effective but differ in dosing convenience:
Valacyclovir 1000 mg orally three times daily for 7 days offers better bioavailability than acyclovir and requires less frequent dosing, which improves patient adherence 4, 5
Acyclovir 800 mg orally five times daily for 7-10 days is effective but requires more frequent dosing, which may reduce compliance 6, 1, 3
Famciclovir 500 mg orally three times daily for 7 days provides similar efficacy to acyclovir with better bioavailability and less frequent administration 6, 7
Critical Timing Considerations
Treatment must be initiated within 72 hours of rash onset for maximum effectiveness in accelerating cutaneous healing and reducing acute pain severity 6, 2, 7
While most evidence supports the 72-hour window, treatment should still be considered even beyond this timeframe in immunocompromised patients or those with severe disease 2, 8
Continue antiviral therapy until all lesions have completely scabbed, not just for an arbitrary 7-day duration—treatment may need extension if active lesions persist 2, 3
Special Population Management
Immunocompromised Patients
Intravenous acyclovir 5 mg/kg every 8 hours is recommended for severe, disseminated, or invasive herpes zoster in immunocompromised hosts 1, 2, 3
Consider temporary reduction or discontinuation of immunosuppressive medications in cases of disseminated disease 1, 2, 3
Monitor closely for cutaneous dissemination and visceral involvement (pneumonia, encephalitis, hepatitis), which necessitate IV therapy 2, 9, 10
Ophthalmic Involvement
Facial zoster with potential cranial nerve involvement requires particular attention due to risk of serious ocular complications including keratitis, iridocyclitis, secondary glaucoma, and vision loss 2, 9
Ophthalmology referral is generally warranted for suspected ocular involvement 8
Important Caveats and Pitfalls
Topical antiviral therapy is substantially less effective than systemic therapy and should not be used 1, 2, 3
Antiviral medications do not eradicate latent virus but control acute symptoms and reduce complications including postherpetic neuralgia 1, 2
Inadequate dosing or premature discontinuation may lead to treatment failure and increased complication risk 3
While antivirals reduce the duration and severity of acute pain, evidence for preventing postherpetic neuralgia is mixed—oral acyclovir did not significantly reduce PHN incidence at 4 or 6 months in meta-analysis 11
Adjunctive Pain Management
For acute neuritis and severe pain, consider analgesics ranging from NSAIDs to opioids as needed 8
Neuropathic pain agents (tricyclic antidepressants, anticonvulsants) may be beneficial for persistent pain 8
Some evidence suggests oral corticosteroids as adjunctive therapy may provide modest benefits in reducing acute pain, though this should be avoided in immunocompromised patients 2, 8
Monitoring and Follow-Up
Monitor for complete healing of all lesions—this is the key clinical endpoint, not calendar days 2, 3
Watch for development of postherpetic neuralgia, particularly in patients over 50 years of age 5
In immunocompromised patients, maintain vigilance for signs of dissemination requiring escalation to IV therapy 2, 10