Valacyclovir (Valtrex) Dosing for Genital Herpes
For genital herpes, the FDA-approved dosing of Valtrex (valacyclovir) is 1 gram twice daily for 10 days for initial episodes, 500 mg twice daily for 3 days for recurrent episodes, and 1 gram once daily or 500 mg once daily for suppressive therapy depending on recurrence frequency. 1
Dosing Recommendations by Clinical Scenario
Initial Episode of Genital Herpes
- Dose: 1 gram twice daily
- Duration: 10 days
- Timing: Most effective when started within 48 hours of symptom onset 1
Recurrent Episodes
- Dose: 500 mg twice daily
- Duration: 3 days
- Timing: Start at first sign or symptom of an episode 1
Suppressive Therapy
For patients with normal immune function:
- Standard dose: 1 gram once daily
- Alternative dose: 500 mg once daily (for patients with ≤9 recurrences per year) 1
For HIV-1 infected patients with CD4+ count ≥100 cells/mm³:
- Dose: 500 mg twice daily 1
Reduction of Transmission
- Dose: 500 mg once daily for the source partner (with history of ≤9 recurrences per year) 1
Renal Dosage Adjustments
Valacyclovir requires dose adjustment in patients with renal impairment:
| Creatinine Clearance (mL/min) | Valacyclovir Dosing |
|---|---|
| ≥50 (normal) | No adjustment needed |
| 30-49 | No adjustment needed |
| 10-29 | 500 mg every 24 hours |
| <10 | 500 mg every 24 hours |
Administration Considerations
- Valtrex may be given without regard to meals 1
- For optimal efficacy in recurrent episodes, initiate treatment at the earliest sign of recurrence (tingling, itching, burning) 1
- Therapy should be initiated at the earliest symptom for best results 1
Clinical Pearls and Pitfalls
- Common Pitfall: Delayed treatment decreases efficacy. Start treatment as soon as possible after symptoms appear 2
- Caution: Underdosing can lead to treatment failure and increased risk of complications 2
- Important: Premature discontinuation of therapy can lead to recurrence or prolonged symptoms 2
- Patient Education: Advise patients to:
- Abstain from sexual activity while lesions are present
- Use condoms during all sexual exposures
- Understand the potential for recurrent episodes and asymptomatic transmission 2
Efficacy Considerations
- Suppressive therapy with valacyclovir reduces recurrence frequency by at least 70-80% in patients with frequent episodes 2
- Once-daily valacyclovir (500 mg) has been shown to be as effective as twice-daily regimens for patients with fewer than 10 recurrences per year 3
- For patients with 10 or more recurrences per year, 1 gram once daily or 500 mg twice daily may be more effective 3
Special Populations
- Immunocompromised patients: May require longer treatment duration and closer monitoring 2
- HIV patients: Higher oral doses may be required, especially with CD4+ counts <200 cells/µL 2
- Pregnant women: Should inform their healthcare providers about genital herpes during pregnancy 2
Valacyclovir offers simplified dosing compared to acyclovir (which requires 5 times daily administration), potentially improving patient adherence while maintaining similar efficacy 4.