What is the dosing of Valacyclovir (Valtrex) for a pediatric patient with herpes labialis (cold sore)?

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From the FDA Drug Label

  1. 2 Pediatric Dosing Recommendations Cold Sores (Herpes Labialis) The recommended dosage of VALTREX for the treatment of cold sores in pediatric patients aged greater than or equal to 12 years is 2 grams twice daily for 1 day taken 12 hours apart.

The recommended dosing for valacyclovir in pediatric patients for cold sores is:

  • 2 grams twice daily for 1 day taken 12 hours apart for patients aged greater than or equal to 12 years. There is no recommended dosage for pediatric patients less than 12 years for cold sores 1.

From the Research

Valacyclovir for pediatric cold sores is typically dosed at 20 mg/kg/dose given three times daily for 5 days, with a maximum dose of 1 gram three times daily, as supported by the most recent and highest quality study 2.

Key Considerations

  • The dosing recommendation is based on the study that evaluated the pharmacokinetics and safety of valacyclovir oral suspension in pediatric patients from 1 month through 11 years of age 2.
  • The study found that a dose of 20 mg/kg of valacyclovir oral suspension produces favorable acyclovir blood concentrations and is well tolerated in children 3 months through 11 years of age 2.
  • For children 12 years and older, the adult dose of 2 grams twice daily for one day can be used.
  • Treatment should be started at the first sign of a cold sore (tingling, burning, or redness) for maximum effectiveness.
  • Side effects are generally mild and may include headache, nausea, or stomach pain.
  • Adequate hydration should be maintained during treatment.

Mechanism of Action

  • Valacyclovir works by inhibiting viral DNA synthesis, preventing the herpes simplex virus from replicating.
  • It's more effective than topical treatments for cold sores and has better bioavailability than acyclovir.

Special Considerations

  • If cold sores recur frequently (more than 6 episodes per year), a preventive regimen might be considered after consultation with a healthcare provider.
  • The safety and efficacy of valacyclovir in pediatric patients have been established, but it's essential to follow the recommended dosing and administration guidelines to minimize the risk of adverse effects.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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