What the FDA labels say about taking them together
Cidofovir and probenecid
Cidofovir's FDA label of October 25, 2023 names probenecid in its boxed warning section; the probenecid label PlainMeds reads does not name cidofovir. The cidofovir label: “TO REDUCE POSSIBLE NEPHROTOXICITY, INTRAVENOUS PREHYDRATION WITH NORMAL SALINE AND ADMINISTRATION OF PROBENECID MUST BE USED WITH EACH CIDOFOVIR INFUSION.”
Check it at the source: the cidofovir FDA label on DailyMed (effective October 25, 2023, Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc.); the probenecid FDA label on DailyMed (effective January 5, 2021, Lannett Company, Inc.).
What does the cidofovir label say about probenecid?
Cidofovir label, boxed warningTO REDUCE POSSIBLE NEPHROTOXICITY, INTRAVENOUS PREHYDRATION WITH NORMAL SALINE AND ADMINISTRATION OF PROBENECID MUST BE USED WITH EACH CIDOFOVIR INFUSION.
Cidofovir label, contraindicationsCidofovir injection is contraindicated in patients with a history of clinically severe hypersensitivity to probenecid or other sulfa-containing medications.
Cidofovir label, drug interactionsDrug 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).
Cidofovir label, warningsIntravenous normal saline hydration and oral probenecid must accompany each cidofovir infusion.
Source: FDA drug label (CIDOFOVIR DIHYDRATE), Heritage Pharmaceuticals Inc. d/b/a Avet Pharmaceuticals Inc., effective October 25, 2023 (SPL set 44966a7e-d777-40fb-956f-d0f31f737848), via openFDA; the full label on DailyMed
What does the probenecid label say about cidofovir?
Probenecid's label (effective January 5, 2021) does not name cidofovir in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Probenecid), Lannett Company, Inc., effective January 5, 2021 (SPL set ab497fd8-00c3-4364-b003-b39d21fbdf38), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Cidofovir | Probenecid | |
|---|---|---|
| Labeled for | n/a | Gout |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | n/a | $0.636 per tablet 500 mg tablet |
| Shortage now | No current entry | No current entry |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once