Vadadustat and Oseltamivir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Oseltamivir
Vadadustat
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased oseltamivir carboxylate exposure and an increased risk of oseltamivir carboxylate-related adverse effect
Interaction Deep Dive
Concomitant use of vadadustat with oseltamivir carboxylate (OAT3 substrate) may increase the exposure of oseltamivir carboxylate, which may increase the risk of adverse reactions related to oseltamivir carboxylate. Effect of vadadustat on pharmacokinetics of OAT3 substrate was studied when coadministered. With vadadustat, the AUC and Cmax of furosemide (OAT3 substrate) increased approximately by 2.0-fold and 1.8-fold respectively. Monitor for signs of adverse reactions of the coadministered oseltamivir carboxylate and adjust oseltamivir carboxylate dosage, if needed1.
Why it happens (mechanism)
Inhibition of OAT3-mediated efflux transport of oseltamivir carboxylate
Literature reports
1 report — tap to read
a) Effect of vadadustat on pharmacokinetics of OAT3 substrate was studied when coadministered. With vadadustat, the AUC and Cmax of furosemide (OAT3 substrate) increased approximately by 2.0-fold and 1.8-fold respectively 1.
Common questions
Can I take Vadadustat and Oseltamivir together?
Increased oseltamivir carboxylate exposure and an increased risk of oseltamivir carboxylate-related adverse effect Always confirm with your pharmacist or prescriber before making any change.
How serious is the Vadadustat and Oseltamivir interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Vadadustat or Oseltamivir need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (1)
- Product Information: VAFSEO(R) oral tablets, vadadustat oral tablets. Akebia Therapeutics (Per Manufacturer), Cambridge, MA, 2024. DailyMed
Keep reading about Oseltamivir
Keep reading about Vadadustat
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Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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