From the Guidelines
Valacyclovir (Valtrex) should be prescribed at a dosage of 500 mg once daily for cold sore suppression. This suppressive therapy is recommended for individuals who experience frequent cold sore outbreaks, generally defined as 6 or more episodes per year 1. The medication should be taken consistently each day, regardless of whether symptoms are present, to maintain effective blood levels.
Key Considerations
- Treatment duration is usually evaluated after 12 months to determine if continued suppression is necessary based on frequency of recurrences.
- Valacyclovir works by converting to acyclovir in the body, which inhibits viral DNA synthesis and replication of herpes simplex virus (HSV-1), the virus responsible for cold sores.
- This suppressive approach can reduce outbreak frequency by approximately 70-80% in most patients.
- Some patients may experience mild side effects including headache, nausea, or dizziness.
- Adequate hydration should be maintained while taking this medication.
- Patients with kidney disease may require dose adjustment, and it's essential to inform your healthcare provider about all medications you're taking to avoid potential interactions.
Special Cases
- For patients with very frequent recurrences (i.e., greater than or equal to 10 episodes per year), valacyclovir 500 mg once a day may be less effective compared to other valacyclovir dosing regimens 1.
- In such cases, alternative dosing regimens, such as valacyclovir 250 mg orally twice a day or valacyclovir 1,000 mg orally once a day, may be considered 1.
From the FDA Drug Label
The recommended dosage of VALTREX for treatment of cold sores is 2 grams twice daily for 1 day taken 12 hours apart. However, this text refers to the treatment of cold sores, not suppression. There is no information in the provided drug labels about the dosing of valacyclovir for cold sore suppression. The FDA drug label does not answer the question.
From the Research
Valacyclovir Dosing for Cold Sore Suppression
- The recommended dosing of valacyclovir (Valtrex) for cold sore suppression is not explicitly stated in the provided studies, but it is mentioned that valacyclovir is approved for once daily dosing for suppressive therapy of herpes labialis (cold sores) 2.
- For chronic daily suppressive therapy, oral antivirals like valacyclovir are the treatment of choice, especially for patients with severe or frequent (six or more episodes per year) recurrences of cold sores 3.
- Valacyclovir has been shown to be safe and effective in the therapy of patients with herpes simplex and herpes zoster, and may be useful in other viral infections, including cold sores 2.
- The use of valacyclovir for cold sore suppression has increased over time, while the use of acyclovir has decreased, indicating a shift towards newer antiviral medications 4.
- Oral antiviral agents like valacyclovir are superior to topical antiviral therapy for episodic treatment of cold sores, and have greater oral bioavailability and are better absorbed than acyclovir, requiring less frequent dosing 3, 5.