Recommended Dosing of Valacyclovir for Herpes Suppression
For suppressive therapy of recurrent genital herpes, the recommended dose of valacyclovir is 500 mg once daily for patients with infrequent recurrences (<10 episodes per year) and 1000 mg once daily for patients with frequent recurrences (≥10 episodes per year). 1, 2
Dosing Recommendations Based on Patient Characteristics
Immunocompetent Patients
- 500 mg once daily for patients with <10 recurrences per year 1, 2, 3
- 1000 mg once daily for patients with ≥10 recurrences per year 1, 2, 3
- Safety and efficacy documented for up to 1 year with valacyclovir 4
HIV-Infected Patients
- 500 mg twice daily for patients with CD4+ count ≥100 cells/mm³ 1
- Higher doses may be beneficial for immunocompromised patients due to potentially more severe and frequent recurrences 4
- Avoid doses of 8g per day in immunocompromised patients due to risk of thrombotic thrombocytopenic purpura/hemolytic uremic syndrome 4, 1
Clinical Considerations
Efficacy
- Daily suppressive therapy reduces recurrence frequency by ≥75% among patients with frequent episodes 4
- Valacyclovir 500 mg once daily appears less effective than other valacyclovir dosing regimens in patients with very frequent recurrences (≥10 episodes per year) 4
- Valacyclovir suppressive therapy is comparable to acyclovir in clinical outcomes but provides increased ease in administration 4, 3
Duration of Therapy
- After 1 year of continuous suppressive therapy, consider discussing discontinuation to assess the patient's psychological adjustment to genital herpes and rate of recurrent episodes 4, 1
- Recurrence frequency may decrease over time in many patients 4
Important Considerations
- Suppressive therapy reduces but does not eliminate asymptomatic viral shedding 4, 1
- No laboratory monitoring is needed for patients on suppressive therapy unless they have substantial renal impairment 1
- Valacyclovir can be given without regard to meals 2
Treatment Failure
- If lesions persist despite appropriate valacyclovir treatment, consider HSV resistance 4, 1
- All acyclovir-resistant strains are also resistant to valacyclovir 4, 1
- For acyclovir-resistant HSV, IV foscarnet (40 mg/kg body weight IV every 8 hours until clinical resolution) is the treatment of choice 4
Special Populations
Pregnancy
- The safety of valacyclovir therapy in pregnant women has not been fully established 4
- Current registry findings do not indicate an increased risk for major birth defects after acyclovir treatment compared to the general population 4
By following these evidence-based dosing recommendations, clinicians can effectively manage herpes suppression while minimizing recurrences and improving patients' quality of life.