Valacyclovir

Name: Valacyclovir Drug Interactions
Creator: Dr. Brian Staiger, PharmD, BCPS

3 interactions

Also sold as: Valtrex Valtrex®

About Valacyclovir

Valacyclovir is an antiviral medication used to treat herpes zoster (shingles) and genital herpes infections. Read the full Valacyclovir drug information page →

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jun 30, 2026 · Editorial policy · Data sources

Sources: FDA prescribing information (Structured Product Labeling), the published literature cited in each entry, DDInter 2.0 (a major open-access drug-interaction database), and legacy DrugBank interaction data distributed by the NIH's RxNav service (decommissioned in 2024) — analyzed and reviewed by our pharmacist team. How we build this library →

Most serious with: Emtricitabine Foscarnet Injection Leflunomide

3 Major

All (3) Major (3)

Major

Valacyclovir Emtricitabine Emtriva Increased emtricitabine exposure and an increased risk of emtricitabine-related adverse effects Details Valacyclovir Foscarnet Injection Foscavir Nephrotoxicity Details Valacyclovir Leflunomide Arava Increased exposure of OAT3 substrate Details

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Educational information only, not medical advice. Always confirm interactions with your pharmacist or prescriber before making any change to your medications.