What is the acute treatment for shingles?

Acute Treatment for Shingles

For acute shingles, initiate oral antiviral therapy with valacyclovir 1 gram three times daily, famciclovir 500 mg every 8 hours, or acyclovir 800 mg five times daily within 72 hours of rash onset, continuing treatment until all lesions have completely scabbed (typically 7-10 days). 1

First-Line Oral Antiviral Options

The three FDA-approved oral antivirals are equally effective for treating acute herpes zoster, with choice based primarily on dosing convenience 2, 3:

• Valacyclovir 1000 mg three times daily for 7 days - Superior bioavailability and most convenient dosing 1
• Famciclovir 500 mg every 8 hours for 7 days - Equally effective with better bioavailability than acyclovir 1, 3
• Acyclovir 800 mg five times daily for 7-10 days - Effective but requires more frequent dosing 1, 2

Critical timing: Treatment must be initiated within 72 hours of rash onset for optimal efficacy in reducing acute pain, accelerating lesion healing, and preventing postherpetic neuralgia, though treatment within 48 hours is ideal 1.

Treatment endpoint: Continue antiviral therapy until all lesions have completely scabbed, not just for an arbitrary 7-day period - this is the key clinical endpoint 1. If lesions remain active beyond 7 days, extend treatment duration 1.

Indications for Intravenous Acyclovir

Switch to IV acyclovir 10 mg/kg every 8 hours for 1:

• Disseminated or invasive herpes zoster (multi-dermatomal or visceral involvement)
• Severely immunocompromised patients (active chemotherapy, HIV with low CD4 counts)
• Complicated facial zoster with suspected CNS involvement
• Severe ophthalmic disease
• Patients unable to tolerate oral medications

Continue IV therapy for minimum 7-10 days and until clinical resolution is attained 1.

Special Population Considerations

Immunocompromised patients:

• Consider IV acyclovir even for uncomplicated disease if severely immunosuppressed 1
• Temporarily reduce immunosuppressive medications when feasible for disseminated disease 1
• May require extended treatment duration beyond 7-10 days as lesions develop over longer periods (7-14 days) and heal more slowly 1
• Monitor for acyclovir resistance if lesions fail to resolve within 7-10 days; consider foscarnet 40 mg/kg IV every 8 hours for resistant cases 1

Facial/ophthalmic involvement:

• Urgent indication for antiviral therapy due to risk of vision-threatening complications and cranial nerve involvement 1
• Consider IV therapy for complicated cases 1

Renal impairment:

• Mandatory dose adjustments to prevent acute renal failure 1
• Monitor renal function at initiation and once or twice weekly during IV acyclovir treatment 1

Adjunctive Pain Management

Antiviral therapy alone does not adequately address acute zoster pain 1:

• Appropriately dosed analgesics (acetaminophen, NSAIDs, or opioids for severe pain)
• Consider adding gabapentin or pregabalin for neuropathic pain
• Tricyclic antidepressants (amitriptyline) may be beneficial

Corticosteroids: Prednisone may be used as adjunctive therapy in select cases of severe, widespread shingles to reduce acute pain, but does NOT prevent postherpetic neuralgia 1. Avoid in immunocompromised patients due to increased risk of disseminated infection 1. Contraindicated in patients with poorly controlled diabetes, history of steroid-induced psychosis, or severe osteoporosis 1.

Common Pitfalls to Avoid

• Do not use topical acyclovir - substantially less effective than systemic therapy and not recommended 1
• Do not stop treatment at exactly 7 days if lesions are still forming or have not completely scabbed 1
• Do not use genital herpes dosing (acyclovir 400 mg TDS) for shingles - this is inadequate for VZV infection 1
• Do not delay treatment waiting for laboratory confirmation in typical presentations 1

Infection Control

Patients should avoid contact with susceptible individuals (pregnant women, immunocompromised persons, those without chickenpox history) until all lesions have crusted, as lesions are contagious 1.

Prevention of Future Episodes

The recombinant zoster vaccine (Shingrix) is recommended for all adults aged 50 years and older, regardless of prior herpes zoster episodes, and can be administered after recovery from acute infection 1.