Simeprevir and Methotrexate Injection: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Simeprevir
Methotrexate Injection
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 exposure of OATP1B1/3 substrate
Interaction Deep Dive
Coadministration of simeprevir (an OATP1B1/3 inhibitor) and an OATP1B1/3 substrate may result in increased exposure of the OATP1B1/3 substrate1.
Why it happens (mechanism)
Inhibition of OATP1B1/3-mediated efflux transport by simeprevir
Common questions
Can I take Simeprevir and Methotrexate Injection together?
Increased exposure of OATP1B1/3 substrate Always confirm with your pharmacist or prescriber before making any change.
How serious is the Simeprevir and Methotrexate Injection 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 Simeprevir or Methotrexate Injection 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: OLYSIO(R) oral capsules, simeprevir oral capsules. Janssen Therapeutics (per manufacturer), Titusville, NJ, 2014.
Keep reading about Simeprevir
Keep reading about Methotrexate Injection
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