What is the recommended treatment for herpes zoster?

Treatment of Herpes Zoster

For uncomplicated herpes zoster (shingles), oral antiviral therapy with valacyclovir 1 gram three times daily for 7 days is the recommended first-line treatment. 1

Treatment Algorithm Based on Disease Severity

Uncomplicated Herpes Zoster

• First-line treatment: Valacyclovir 1 gram orally three times daily for 7 days 1, 2
• Alternative options:
  • Acyclovir 800 mg orally five times daily for 7 days 1
  • Famciclovir 500 mg orally three times daily for 7 days 3
• Treatment should be initiated within 72 hours of rash onset for maximum effectiveness 2, 4
• Continue treatment until all lesions have scabbed 1

Disseminated or Invasive Herpes Zoster

• Recommended treatment: Intravenous acyclovir 5-10 mg/kg every 8 hours 1
• Temporary reduction in immunosuppressive medication if applicable 1
• Continue treatment until clinical resolution is attained 1
• Switch to oral therapy once clinical improvement occurs 1

Special Populations

Immunocompromised Patients

• Valacyclovir 1 gram three times daily for 7 days is effective in immunocompromised patients 5
• Higher dosages (valacyclovir 2 grams three times daily) have not shown additional benefit 5
• Consider longer treatment duration if healing is delayed 1
• Monitor closely for dissemination and complications 1

Elderly Patients

• Valacyclovir has shown better efficacy than acyclovir in patients ≥50 years old 4
• Median duration of post-herpetic neuralgia is significantly reduced with valacyclovir (38 days) compared to acyclovir (51 days) 4
• Dosage adjustment may be needed for renal impairment 2

Clinical Benefits of Treatment

• Accelerates rash healing 4, 6
• Reduces acute pain during the eruptive phase 4, 6, 3
• Decreases the duration of post-herpetic neuralgia 4, 6
• Reduces the proportion of patients with persistent pain at 6 months (19.3% vs 25.7% with acyclovir) 4

Important Considerations

• Therapy is most effective when initiated within 48-72 hours of rash onset 2, 4
• However, treatment may still be beneficial when started later than 72 hours after rash onset, especially in patients with new lesion formation or immunocompromised status 3
• Treatment should be continued until all lesions have scabbed 1
• No significant benefit has been shown for extending acyclovir treatment beyond 7 days 7

Common Pitfalls and Caveats

• Failure to initiate treatment promptly (within 72 hours of rash onset) significantly reduces efficacy 2, 4
• Inadequate dosing frequency (valacyclovir offers simpler dosing than acyclovir) 4, 6, 3
• Not continuing treatment until all lesions have scabbed 1
• Antiviral therapy reduces but does not eliminate the risk of post-herpetic neuralgia 4, 3
• Not adjusting dosage in patients with renal impairment 2

Prevention of Varicella Zoster in Susceptible Patients

• For varicella-susceptible patients exposed to active varicella zoster infection:
  • Varicella zoster immunoglobulin within 96 hours of exposure 1
  • If immunoglobulin is unavailable or >96 hours have passed, a 7-day course of oral acyclovir begun 7-10 days after exposure 1