What is the correct dose of valacyclovir (Valtrex) for a genital outbreak of Herpes Simplex (HSV)?

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: May 28, 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.

From the Guidelines

For a genital herpes outbreak, the recommended dose of valacyclovir is 1,000 mg orally once a day, as this is one of the options listed in the guidelines for treatment of sexually transmitted diseases 1. When considering the treatment of genital herpes, it's essential to look at the most recent and highest quality studies.

  • The dose of valacyclovir can vary depending on the frequency and severity of outbreaks, as well as the patient's overall health.
  • For initial episodes, the dose is typically higher, while for recurrent outbreaks, a lower dose may be sufficient.
  • Suppressive therapy is also an option for patients with frequent outbreaks, and the dose for this can vary depending on the patient's specific needs 1. Some key points to consider when taking valacyclovir include:
  • Taking the medication with or without food
  • Maintaining adequate hydration
  • Starting treatment as soon as possible after noticing symptoms
  • Potential side effects, such as headache, nausea, and abdominal pain
  • The need for dosage adjustments in patients with kidney problems It's also important to note that valacyclovir works by converting to acyclovir in the body, which inhibits viral DNA synthesis and replication of the herpes simplex virus 1.
  • The medication is effective in preventing recurrences and reducing the severity of symptoms.
  • Daily anti-HSV suppressive therapy can also result in a decrease in HIV concentration in plasma and anal and genital secretions, although the clinical benefit of this is not yet fully understood 1.

From the FDA Drug Label

  1. 1 Adult Dosing Recommendations Genital Herpes Initial Episode: The recommended dosage of VALTREX for treatment of initial genital herpes is 1 gram twice daily for 10 days. Recurrent Episodes: The recommended dosage of VALTREX for treatment of recurrent genital herpes is 500 mg twice daily for 3 days

The correct dose of valacyclovir for a genitalia outbreak of herpetic simplex is 500 mg twice daily for 3 days for recurrent episodes, or 1 gram twice daily for 10 days for initial episodes, as specified for recurrent and initial genital herpes treatment, respectively 2.

  • Initial Episode: 1 gram twice daily for 10 days
  • Recurrent Episodes: 500 mg twice daily for 3 days

From the Research

Valacyclovir Dosage for Genital Herpes

The correct dose of valacyclovir for a genitalia outbreak of herpetic simplex is as follows:

  • For episodic treatment of recurrent genital herpes, valacyclovir can be taken at a dose of 500 mg twice daily for 3 days 3
  • For suppressive therapy, valacyclovir dosages of ≥ 500 mg daily are recommended for suppression of genital herpes recurrences in immunocompetent individuals 4
  • Once daily valacyclovir (1000 mg, 500 mg and 250 mg) has been shown to produce statistically significant suppression of disease recurrence 4

Considerations for Treatment

When choosing a treatment approach, the following factors should be considered:

  • The severity and frequency of outbreaks
  • The patient's immunocompetence status
  • The potential for antiviral resistance
  • The cost and ease of dosing of the medication
  • The patient's preference for episodic or suppressive therapy 5, 6, 7

Safety and Efficacy

Valacyclovir has been shown to be safe and effective in the treatment of genital herpes, with a low risk of adverse effects 4, 3, 6 However, high-dose valacyclovir therapy (8 g/day) has been associated with a potentially fatal thrombotic microangiopathy (TMA)-like syndrome in some immunocompromised patients 4

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.