What is the recommended treatment for Varicella zoster (chickenpox/shingles)?

Treatment of Varicella Zoster (Chickenpox/Shingles)

The recommended treatment for varicella zoster infections depends on the clinical presentation, with oral acyclovir, valacyclovir, or famciclovir being the first-line treatments for uncomplicated herpes zoster (shingles), while intravenous acyclovir is recommended for severe or disseminated disease. 1

Treatment Recommendations Based on Clinical Presentation

Uncomplicated Herpes Zoster (Shingles)

• Treat with oral acyclovir or valacyclovir until all lesions have scabbed 1
• Recommended dosing regimens:
  • Acyclovir: 800 mg orally 5 times daily for 7-10 days 2
  • Valacyclovir: 1000 mg orally 3 times daily for 7 days 3
  • Famciclovir: 500 mg orally 3 times daily for 7 days 4

Disseminated or Invasive Herpes Zoster

• Treat with intravenous acyclovir 1
• Temporarily reduce immunosuppressive medication if applicable 1
• Continue treatment until all lesions have scabbed 1
• Consider switching to oral therapy once clinical response is observed 1

Primary Varicella Infection (Chickenpox)

• Treatment options:
  • For children (2 years and older): Acyclovir 20 mg/kg per dose orally 4 times daily for 5 days 2
  • For adults and children over 40 kg: Acyclovir 800 mg orally 4 times daily for 5 days 2
  • For immunocompromised patients: Intravenous acyclovir 2

Special Populations

Immunocompromised Patients

• High-dose intravenous acyclovir is the treatment of choice 1
• Oral therapy should be reserved for mild cases or to complete therapy after clinical response to IV treatment 1
• For kidney transplant recipients:
  • Uncomplicated herpes zoster: Oral acyclovir or valacyclovir until all lesions have scabbed 1
  • Disseminated or invasive disease: Intravenous acyclovir with temporary reduction in immunosuppressive medication 1

HIV-Infected Individuals

• No specific differences in treatment recommendations compared to immunocompetent hosts 1
• May require longer treatment duration (7-14 days) and slower healing should be expected 1

Prevention Strategies

Post-Exposure Prophylaxis

• For susceptible individuals (no history of chickenpox/shingles or seronegative for VZV) after exposure to active VZV infection 1:
  • Varicella zoster immunoglobulin within 96 hours of exposure 1
  • If immunoglobulin is not available or more than 96 hours have passed, consider 7-day course of oral acyclovir begun 7-10 days after exposure 1

Prevention of Recurrence

• No drug has been proven to prevent the recurrence of shingles in immunocompromised or HIV-infected persons 1

Clinical Pearls and Pitfalls

• Treatment should ideally be initiated within 72 hours of rash onset for maximum effectiveness, though later treatment may still provide benefit 3
• Antiviral therapy reduces acute pain, accelerates lesion healing, and may reduce the risk of postherpetic neuralgia 3, 4
• For patients with renal impairment, dose adjustment of acyclovir is necessary 2
• Chronic suppressive therapy is not required after lesions resolve, unlike with herpes simplex virus infections 1
• Resistance to acyclovir can develop, particularly in immunocompromised patients, requiring alternative therapies such as foscarnet 5

Emerging Treatments

• Newer antiviral agents showing promise include:
  • Amenamevir (helicase-primase inhibitor, approved in Japan) 6
  • Valnivudine hydrochloride (FV-100) and valomaciclovir stearate (in advanced development) 6
  • These newer agents may address limitations of current therapies, particularly in controlling herpes zoster pain and preventing postherpetic neuralgia 6