What the FDA labels say about taking them together
Ribavirin and zidovudine
Ribavirin's FDA label of February 6, 2024 names zidovudine in its drug interactions section, and zidovudine's label names ribavirin too. The zidovudine label: “… Exacerbation of anemia has been reported in HIV-1/HCV co-infected patients receiving ribavirin and zidovudine.”
Check it at the source: the ribavirin FDA label on DailyMed (effective February 6, 2024, Aurobindo Pharma Limited); the zidovudine FDA label on DailyMed (effective February 10, 2025, Aurobindo Pharma Limited).
What does the ribavirin label say about zidovudine?
Ribavirin label, drug interactionsInhibitors (NRTIs) In vitro data indicate ribavirin reduces phosphorylation of lamivudine, stavudine, and zidovudine.
Ribavirin label, warnings and precautionsAll 14 patients were on NRTIs, including stavudine, didanosine, abacavir, zidovudine, and lamivudine.
Source: FDA drug label (Ribavirin), Aurobindo Pharma Limited, effective February 6, 2024 (SPL set eee304d0-c2ea-44f4-97d9-92a414d31b6c), via openFDA; the full label on DailyMed
What does the zidovudine label say about ribavirin?
Zidovudine label, drug interactionsNucleoside Analogues Affecting DNA Replication Some nucleoside analogues affecting DNA replication, such as ribavirin, antagonize the in vitro antiviral activity of zidovudine against HIV-1; concomitant use of such drugs should be avoided.
Zidovudine label, warnings and precautionsWARNINGS AND PRECAUTIONS See boxed warning for information about the following: hematologic toxicity, myopathy, and lactic acidosis and severe hepatomegaly. ( 5.1 , 5.2 , 5.3 ) Exacerbation of anemia has been reported in HIV-1/HCV co-infected patients receiving ribavirin and zidovudine.
Retrovir label (ViiV Healthcare Company, November 13, 2024), warnings and precautionsDiscontinue RETROVIR as medically appropriate and consider dose reduction or discontinuation of interferon alfa, ribavirin, or both.
Source: FDA drug label (Retrovir, NDA019655), ViiV Healthcare Company, effective November 13, 2024 (SPL set 6df09f15-b102-431c-adde-d7aeef6f5d84), via openFDA
Source: FDA drug label (Zidovudine), Aurobindo Pharma Limited, effective February 10, 2025 (SPL set 51abd2ce-6be1-412d-b806-5f24935ac5e3), 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
| Ribavirin | Zidovudine | |
|---|---|---|
| Labeled for | Hepatitis C | HIV |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.451 per tablet 200 mg tablet | $0.464 per tablet 300 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