What is the treatment for herpes simplex virus (HSV) infection in young children?

Treatment of Body Herpes in Young Children

For body herpes (HSV) infections in young children, oral acyclovir at a dose of 20 mg/kg body weight (maximum 400 mg per dose) three times daily for 5-10 days is the recommended first-line treatment for mild infections. 1

Treatment Algorithm Based on Severity

Mild Symptomatic Infections

• Oral acyclovir: 20 mg/kg body weight (maximum 400 mg per dose) three times daily for 5-10 days 2, 1
• Continue treatment until lesions completely heal
• Ensure adequate hydration during treatment

Moderate to Severe Infections

1. Initial treatment: Intravenous acyclovir 5-10 mg/kg body weight three times daily 2
2. After lesions begin to regress: Switch to oral acyclovir at the same dose as for mild infections 2
3. Duration: Continue therapy until lesions completely heal 2

Disseminated or CNS Disease

• Intravenous acyclovir: 10 mg/kg body weight three times daily for 21 days 2
• For children outside the neonatal period with CNS involvement 2

Special Considerations

Neonatal HSV Infections

• Skin, eye, or mouth disease: IV acyclovir 20 mg/kg body weight three times daily for 14 days 2
• CNS or disseminated disease: IV acyclovir 20 mg/kg body weight three times daily for 21 days 2
• For neonatal CNS disease: Repeat CSF HSV DNA PCR at days 19-21 of therapy; do not stop acyclovir until repeat CSF HSV DNA PCR is negative 2

Acyclovir-Resistant HSV Infections

• Foscarnet: 40 mg/kg body weight per dose IV three times daily or 60 mg/kg body weight per dose IV twice daily 2

Alternative Medications

While acyclovir is the primary treatment for children with HSV infections, alternative medications may be considered in specific situations:

• Valacyclovir: Approved for use in adults and adolescents but has limited data in children under 12 years 2, 3

  • Not established for use in children under 12 years with cold sores 3
  • Not recommended for children under 18 years with genital herpes 3

• Famciclovir: Approved for adults and adolescents but lacks pediatric preparation and dosing data 2, 4

  • Not recommended for children as efficacy has not been established 4

Important Clinical Pearls

1. Early treatment initiation: Start antiviral therapy at the earliest sign of infection for maximum effectiveness 1

2. Hydration: Maintain adequate hydration during treatment, especially with oral lesions that may make drinking painful 1

3. Monitoring: Watch for potential adverse effects, including:

   • Gastrointestinal symptoms (nausea, vomiting)
   • Headache
   • Rarely, neutropenia with prolonged use 1

4. Dose adjustment: Adjust dosage as the child grows to prevent subtherapeutic levels 1

5. Renal function: Consider dose reduction in patients with impaired renal function 1

6. Avoid topical corticosteroids: These can potentiate HSV infection 1

7. Common pitfalls:

   • Delayed treatment initiation
   • Inadequate dosing
   • Insufficient treatment duration
   • Overlooking systemic infection 1

For recurrent episodes, consider episodic therapy started at the first sign of prodrome. For frequent recurrences (≥6 episodes per year), prophylactic therapy with daily acyclovir may be considered 1.