Acyclovir and Cidofovir Interaction

Drug interaction information between Acyclovir and Cidofovir.

Acyclovir and Cidofovir have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Acyclovir and Cidofovir. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.

Drug A

Acyclovir

Antiviral (Nucleoside Analog)

Drug B

Cidofovir

Antiviral (Nucleotide Analog)

How They Interact

Probenecid is given with cidofovir and can slow down the removal of acyclovir through the kidneys. This can lead to an increase in the amount of acyclovir in your blood.

FDA Label Information

Drug Interactions Probenecid Probenecid is known to interact with the metabolism or renal tubular excretion of many drugs (e.g., acetaminophen, acyclovir, angiotensin-converting enzyme inhibitors, aminosalicylic acid, barbiturates, benzodiazepines, bumetanide, clofibrate, methotrexate, famotidine, furosemide, nonsteroidal anti-inflammatory agents, theophylline, and zidovudine).

Frequently Asked Questions

What SPL severity band is on file for Acyclovir + Cidofovir?

Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.

Which drug in this pair has the larger labeled-interaction portfolio?

Cidofovir has 16 labeled pairs on file vs Acyclovir's 7. In the minor band specifically: Acyclovir has 7 (also Bictegravir, Emtricitabine/Tenofovir, Meperidine, Tenofovir Disoproxil); Cidofovir has 11 (also Furosemide, Famotidine, Acetaminophen, Methotrexate).

What mechanism field is on file for Acyclovir and Cidofovir?

Probenecid is given with cidofovir and can slow down the removal of acyclovir through the kidneys. This can lead to an increase in the amount of acyclovir in your blood.

Cidofovir carries more major-labeled pairs than Acyclovir

SPL source-record counts only. This page's band is minor · classes on file: Acyclovir (Antiviral (Nucleoside Analog)); Cidofovir (Antiviral (Nucleotide Analog)).

Cidofovir has 5 major-labeled pairs vs Acyclovir's 0. This page itself is in the minor band, not the major band.

Acyclovir

0 major · 0 moderate · 7 minor · 7 total

Cidofovir

5 major · 0 moderate · 11 minor · 16 total

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.