Valacyclovir Dosing for Herpes Simplex Virus Infections
The FDA-approved dosing for valacyclovir in herpes simplex virus infections varies by clinical presentation: for initial genital herpes episodes, 1 gram twice daily for 10 days; for recurrent episodes, 500 mg twice daily for 3 days; and for suppressive therapy, 1 gram once daily (or 500 mg once daily for patients with ≤9 recurrences per year). 1
Dosing by Clinical Presentation
Initial Episode of Genital Herpes
- 1 gram twice daily for 10 days 1
- Therapy is most effective when started within 48 hours of symptom onset 1
Recurrent Episodes of Genital Herpes
- 500 mg twice daily for 3 days 1
- Initiate at first sign or symptom of an episode 1
- Early treatment initiation is crucial for maximizing effectiveness 2
Suppressive Therapy for Recurrent Genital Herpes
- For immunocompetent patients:
- For HIV-infected patients with CD4+ ≥100 cells/mm³:
Cold Sores (Herpes Labialis)
- 2 grams twice daily for 1 day (taken 12 hours apart) 1
- Initiate at earliest symptom (tingling, itching, or burning) 1
Special Considerations
Renal Impairment Dosage Adjustments
Dosage must be adjusted based on creatinine clearance:
| Creatinine Clearance (mL/min) | Dosage Adjustment |
|---|---|
| ≥50 (normal) | No adjustment needed |
| 30-49 | No adjustment needed for most indications |
| 10-29 | 500 mg every 24 hours |
| <10 | 500 mg every 24 hours |
Pediatric Dosing
- Cold Sores: For patients ≥12 years: 2 grams twice daily for 1 day 1
- For children <12 years: Oral suspension may be prepared from 500 mg tablets 1
Immunocompromised Patients
- Higher doses and longer treatment durations may be required 2
- Treatment should continue until complete healing of lesions 2
Treatment Duration and Monitoring
- For recurrent episodes, treatment should be initiated at the first sign of prodrome 2, 1
- Patients should continue treatment for the full prescribed duration even if symptoms improve 2
- Self-medication at first sign of prodrome can reduce delay in treatment initiation 2
Patient Education
- Wash hands before and after application 2
- Apply medication to cover all lesions completely 2
- Abstain from sexual activity during outbreaks or prodromal symptoms 2
- Use condoms consistently to reduce transmission risk 2
- Be aware of asymptomatic viral shedding and transmission risk 2
Symptomatic Relief
- Topical anesthetics, warm sitz baths, oral analgesics can provide pain relief 2
- Keep lesions clean and dry 2
Valacyclovir offers the advantage of less frequent dosing compared to acyclovir due to its superior bioavailability, potentially improving treatment adherence while maintaining equivalent clinical efficacy 3, 4.