What is the generic name for Valtrex?

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Generic Name for Valtrex

The generic name for Valtrex is valacyclovir (or valacyclovir hydrochloride). 1

Chemical and Pharmaceutical Details

Valtrex is the brand name for valacyclovir hydrochloride, which is the hydrochloride salt of the L-valyl ester of acyclovir. 1 Valacyclovir functions as a prodrug that is rapidly converted to acyclovir after oral administration through first-pass intestinal and/or hepatic metabolism. 2, 1

Key Pharmacological Characteristics

  • Valacyclovir is a valine ester of acyclovir with enhanced absorption after oral administration 2
  • The absolute bioavailability of acyclovir after valacyclovir administration is 54.5% ± 9.1%, which is significantly higher than oral acyclovir alone 1
  • After absorption, valacyclovir is nearly completely converted to acyclovir and L-valine 1

Clinical Context

Multiple guidelines consistently refer to both the brand name (Valtrex) and generic name (valacyclovir) interchangeably when discussing treatment regimens for:

  • Genital herpes (first episode, recurrent episodes, and suppressive therapy) 2
  • Herpes labialis (cold sores) 3
  • Herpes zoster (shingles) 4, 5
  • HSV prophylaxis in immunocompromised patients 5

The chemical formula is C₁₃H₂₀N₆O₄•HCl with a molecular weight of 360.80. 1 Valacyclovir hydrochloride appears as a white to off-white powder with maximum water solubility of 174 mg/mL at 25°C. 1

References

5
Guideline

prevention and treatment of cancer-related infections.

Journal of the National Comprehensive Cancer Network : JNCCN, 2012

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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.