Valtrex (Valacyclovir) Dosage for Genital Herpes
For genital herpes treatment, the recommended Valtrex dosage 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 patients with 9 or fewer recurrences per year) for suppressive therapy. 1
Initial Genital Herpes Episode
- Dosage: 1 gram twice daily for 10 days 1
- Therapy is most effective when started within 48 hours of symptom onset
- Complete the full course even if symptoms improve before completion
Recurrent Episodes
- Dosage: 500 mg twice daily for 3 days 1
- Start treatment at the first sign or symptom of an episode (tingling, itching, burning)
- A 3-day course is as effective as a 5-day course for recurrent episodes 2
Suppressive Therapy
For patients with normal immune function:
- Primary dosage: 1 gram once daily 1
- Alternative dosage: 500 mg once daily (for patients with ≤9 recurrences per year) 1
For HIV-infected patients:
- Dosage: 500 mg twice daily (for patients with CD4+ count ≥100 cells/mm³) 1
Transmission Reduction
- Dosage: 500 mg once daily for the source partner (for those with ≤9 recurrences per year) 1
Special Populations and Considerations
Renal Impairment
Dosage adjustments are necessary for patients with renal impairment based on creatinine clearance 3:
| Creatinine Clearance (mL/min) | Dose Adjustment |
|---|---|
| >25 | No adjustment needed |
| 10-25 | Reduce frequency based on dose |
| 0-10 | Further reduction in frequency |
Immunocompromised Patients
- May require longer treatment duration and closer monitoring 3
- HIV-infected patients should receive 500 mg twice daily for suppressive therapy 1
Pregnant Patients
- Acyclovir (and by extension, valacyclovir) has an established safety profile during pregnancy 3
Patient Education
- Advise abstaining from sexual activity while lesions are present 3
- Educate about asymptomatic viral shedding and transmission risk 3
- Encourage consistent condom use during all sexual exposures 3
Clinical Pearls and Pitfalls
- Timing matters: Starting treatment within 48 hours of symptom onset maximizes effectiveness 1
- Convenience advantage: Once-daily valacyclovir (1000 mg) is as effective as twice-daily 500 mg dosing for episodic treatment 4
- Dosing flexibility: For suppressive therapy, there is a dose-response relationship across once-daily valacyclovir regimens 5
- Treatment failure: If no improvement is seen after 3-7 days, consider incorrect diagnosis, co-infection, HIV infection, poor medication adherence, or antiviral resistance 3
Valacyclovir can be taken without regard to meals, making it convenient for patients to incorporate into their daily routine 1.