What is the recommended dose of Valtrex (valacyclovir) for treating shingles?

Valtrex Dosing for Shingles

For immunocompetent adults with shingles, the recommended dose of Valtrex (valacyclovir) is 1 gram orally three times daily for 7 days, initiated within 72 hours of rash onset. 1

Standard Dosing Regimen

• Valacyclovir 1 gram orally three times daily for 7 days is the FDA-approved dose for herpes zoster treatment 1
• Treatment should be initiated at the earliest sign or symptom of herpes zoster and is most effective when started within 48 hours of rash onset 1
• Continue treatment until all lesions have scabbed, which is the key clinical endpoint—not an arbitrary 7-day duration 2
• If lesions remain active beyond 7 days, extend treatment duration until complete scabbing occurs 2

Alternative Dosing Considerations

• Valacyclovir 1.5 grams twice daily for 7 days has been studied and shown to be safe and effective, with the advantage of twice-daily dosing potentially improving patient compliance 3
• This twice-daily regimen demonstrated equivalent efficacy to three-times-daily dosing for reduction of zoster-associated pain and abnormal sensations 3

Special Populations and Escalation

Immunocompromised Patients

• Severely immunocompromised patients (such as those on active chemotherapy or with advanced HIV) require intravenous acyclovir 10 mg/kg every 8 hours rather than oral valacyclovir 2
• Treatment should continue for a minimum of 7-10 days and until clinical resolution is attained 2

Disseminated or Invasive Disease

• Multi-dermatomal involvement, visceral involvement, or suspected CNS complications require immediate escalation to intravenous acyclovir 2
• Consider temporary reduction in immunosuppressive medications if applicable 2

Renal Impairment

• Dose adjustments are mandatory based on creatinine clearance to prevent acute renal failure 2
• Monitor renal function closely during therapy 2

Critical Treatment Principles

• Do not use topical acyclovir—it is substantially less effective than systemic therapy 2
• Treatment initiated beyond 72 hours may still provide benefit, particularly for pain reduction, though earlier treatment is optimal 4
• Valacyclovir accelerates resolution of zoster-associated pain and postherpetic neuralgia more effectively than standard acyclovir dosing 5, 4
• Patients should avoid contact with susceptible individuals (those who haven't had chickenpox) until all lesions have crusted 2

Comparative Efficacy

• Valacyclovir 1000 mg three times daily demonstrates superior pain resolution compared to acyclovir 800 mg five times daily, with 23% better outcomes at day 29 5
• The improved bioavailability of valacyclovir (3-5 fold higher than oral acyclovir) allows for less frequent dosing while maintaining therapeutic acyclovir concentrations 6
• Valacyclovir and famciclovir 500 mg three times daily show similar efficacy for herpes zoster treatment 4