Ritonavir and Everolimus: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Ritonavir
Everolimus
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 everolimus exposure and an increased risk of immunosuppressant-related adverse effects
Interaction Deep Dive
Coadministration of everolimus and ritonavir (Viekira Pak™) is contraindicated as this may increase the risk of serious and/or life threatening immunosuppressant-related adverse effects4. Avoid coadministration of everolimus with ritonavir, a dual strong CYP3A4 and P-gp inhibitor, due to the potential for elevated everolimus exposure 32. If concurrent therapy is necessary in transplant recipients, closely monitor everolimus whole blood trough levels 1.
Why it happens (mechanism)
Inhibition of CYP3A4-mediated metabolism and P-gp efflux transport of everolimus
Common questions
Can I take Ritonavir and Everolimus together?
Increased everolimus exposure and an increased risk of immunosuppressant-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Ritonavir and Everolimus interaction?
It is rated contraindicated. These should generally not be used together.
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 Ritonavir or Everolimus 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 (4)
- Product Information: ZORTRESS(R) oral tablets, everolimus oral tablets. Novartis Pharmaceuticals Corporation (per manufacturer), East Hanover, NJ, 2015. DailyMed
- Product Information: AFINITOR DISPERZ® tablets for oral suspension, everolimus tablets for oral suspension. Novartis Pharmaceuticals Corporation, East Hanover, NJ, 2026. DailyMed
- Product Information: AFINITOR® oral tablets, everolimus oral tablets. Novartis Pharmaceuticals Corporation, East Hanover, NJ, 2026. DailyMed
- Product Information: VIEKIRA PAK oral tablets, ombitasvir, paritaprevir, ritonavir, dasabuvir oral tablets. AbbVie Inc (per FDA), North Chicago, IL, 2017.
Keep reading about Ritonavir
Keep reading about Everolimus
These medications also interact with supplements
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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