Acyclovir

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

25 interactions 535 cited references

Also sold as: Avaclyr Sitavig Sitavig® Zovirax Zovirax® Capsules Zovirax® Tablets

About Acyclovir

Acyclovir is an antiviral medication used to treat chickenpox, shingles, and genital herpes infections. Read the full Acyclovir drug information page →

Medically reviewed by Dr. Brian Staiger, PharmD, BCPS · Updated Jul 11, 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: Fezolinetant Bupropion Clomipramine Dichlorphenamide Emtricitabine Fexinidazole

1 Contraindicated 18 Major 5 Moderate 1 Minor

All (25) Contraindicated (1) Major (18) Moderate (5) Minor (1)

Moderate

Acyclovir Fosphenytoin Cerebyx Decreased phenytoin plasma concentrations and potential increased seizure activity Details Acyclovir Meperidine Demerol Increased meperidine and its metabolite normeperidine exposure Details Acyclovir Phenytoin Dilantin Decreased phenytoin plasma concentrations and potential increased seizure activity Details Acyclovir Probenecid Increased OAT3 substrate exposure Details Acyclovir Valproic Acid Depakene® Decreased valproic acid plasma concentrations and potential increased seizure activity 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.