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Valacyclovir

Generic Name: Valacyclovir Hydrochloride

Brand Names: Valtrex

Valacyclovir is an antiviral medication used to treat herpes infections including cold sores, shingles, and genital herpes.

Antiviral

What It's Used For

Valacyclovir is prescribed for:

  • Cold sores (herpes labialis)
  • Genital herpes treatment and suppression
  • Shingles (herpes zoster)
  • Chickenpox in immunocompetent patients
  • CMV prophylaxis in transplant patients

It's a prodrug of acyclovir with better oral absorption.

Side Effects

Common side effects:

  • Headache
  • Nausea
  • Abdominal pain
  • Dizziness

Serious side effects:

  • Thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS) in immunocompromised
  • Acute renal failure
  • CNS effects (confusion, hallucinations)

Additional Information

What is Valacyclovir?

Valacyclovir is an oral antiviral that converts to acyclovir in the body, with superior bioavailability.

Herpes Suppression

Daily suppressive therapy can:

  • Reduce outbreaks by 70-80%
  • Decrease viral shedding
  • Reduce transmission risk to partners

Shingles Timing

Most effective when started within 72 hours of rash onset for shingles.

For more information, see MedlinePlus.

Medical Disclaimer: This information is for educational purposes only and should not be considered medical advice. Always consult with your healthcare provider before starting, stopping, or changing any medication. Your doctor can provide personalized recommendations based on your specific health condition and medical history.

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