What is the recommended Valtrex (valacyclovir) treatment regimen for herpes flareups?

Medical Advisory BoardAll articles are reviewed for accuracy by our Medical Advisory Board
Educational purpose only • Exercise caution as content is pending human review
Article Review Status
Submitted
Under Review
Approved

Last updated: November 22, 2025View editorial policy

Personalize

Help us tailor your experience

Which best describes you? Your choice helps us use language that's most understandable for you.

Valtrex Treatment Regimen for Herpes Flareups

For recurrent genital herpes flareups, treat with valacyclovir 500 mg orally twice daily for 3 days, initiated at the first sign of prodrome or lesion onset. 1, 2

Episodic Treatment for Recurrent Episodes

Standard Regimen

  • Valacyclovir 500 mg orally twice daily for 3 days is the FDA-approved and CDC-recommended first-line treatment for recurrent genital herpes episodes 1, 2
  • This 3-day regimen is the shortest FDA-approved course for episodic treatment, offering superior convenience compared to older acyclovir regimens 2, 3

Alternative Regimens (if valacyclovir unavailable)

  • Acyclovir 400 mg orally three times daily for 5 days 1
  • Acyclovir 800 mg orally twice daily for 5 days 1
  • Acyclovir 200 mg orally five times daily for 5 days 1
  • Famciclovir 125 mg orally twice daily for 5 days 1

Critical Timing Considerations

  • Treatment must be initiated during prodrome or within 1 day of lesion onset for maximum benefit 1, 4
  • Provide patients with a prescription or medication supply to enable immediate self-initiation at first symptoms 4
  • Efficacy drops significantly if treatment is delayed beyond 24 hours of symptom onset 1

Suppressive Therapy for Frequent Recurrences

When to Consider Suppression

  • Recommend daily suppressive therapy for patients with ≥6 recurrences per year 1
  • Suppressive therapy reduces recurrence frequency by ≥75% 1, 4

Suppressive Regimens

  • Valacyclovir 1 gram orally once daily (standard dose) 1, 2
  • Valacyclovir 500 mg orally once daily (alternative for patients with <10 recurrences per year) 1, 2, 5
  • Acyclovir 400 mg orally twice daily (if valacyclovir unavailable) 1
  • Famciclovir 250 mg orally twice daily (alternative option) 1

Duration and Reassessment

  • Suppressive therapy is safe for up to 6 years with acyclovir and 1 year with valacyclovir based on documented safety data 1, 4
  • After 1 year of continuous suppression, consider discontinuation to reassess recurrence frequency 1

Special Populations and Considerations

HIV-Infected Patients

  • For HIV-infected patients with CD4+ count ≥100 cells/mm³, use valacyclovir 500 mg twice daily for suppressive therapy 2
  • These patients may require more aggressive therapy than immunocompetent individuals 6

Renal Impairment

  • Dosage adjustment is necessary for patients with reduced renal function 2
  • Valacyclovir should be used with caution in patients with impaired renal clearance 7

Immunocompromised Patients

  • Suspect acyclovir resistance if lesions do not begin to resolve within 7-10 days of therapy 1
  • For proven or suspected resistance, use foscarnet 40 mg/kg IV every 8 hours 1
  • Avoid valacyclovir 8 grams per day in immunocompromised patients due to risk of hemolytic uremic syndrome/thrombotic thrombocytopenic purpura 1

Critical Pitfalls to Avoid

What NOT to Use

  • Never use topical acyclovir - it is substantially less effective than oral therapy and should be avoided 1, 4, 6
  • Topical formulations provide minimal clinical benefit compared to systemic treatment 6

Patient Education Requirements

  • Counsel that antiviral medications control symptoms but do not eradicate latent virus or prevent all future recurrences 1, 4
  • Advise abstinence from sexual activity when lesions or prodromal symptoms are present 1
  • Inform patients that asymptomatic viral shedding can occur, potentially leading to transmission even without visible lesions 1, 4
  • Recommend condom use during all sexual exposures with new or uninfected partners 1

When to Extend or Escalate Treatment

  • Consider extended treatment beyond the standard course if symptoms persist beyond 5 days 1
  • Evaluate for potential co-infections if discharge and pelvic pain persist despite treatment 1
  • For severe disease requiring hospitalization (disseminated infection, encephalitis, pneumonitis, hepatitis), use IV acyclovir 5-10 mg/kg every 8 hours instead of oral therapy 6

Herpes Labialis (Cold Sores)

If the flareup involves herpes labialis rather than genital herpes:

  • Valacyclovir 2 grams orally twice daily for 1 day (taken 12 hours apart) 4, 2
  • This single-day, high-dose regimen is specific to cold sores and differs significantly from genital herpes treatment 2
  • Must be initiated at earliest symptom (tingling, itching, burning) 4, 2

References

Guideline

Treatment for Recurrent Genital Herpes

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Valacyclovir for Recurrent HSV-1 Labial Episode

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Guideline

Valacyclovir Dosing for Herpes Zoster

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

Have a follow-up question?

Our Medical A.I. is used by practicing medical doctors at top research institutions around the world. Ask any follow up question and get world-class guideline-backed answers instantly.