Pemigatinib and Nafcillin Injection: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Pemigatinib
Nafcillin 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
Decreased pemigatinib exposure and risk of reduced efficacy
Interaction Deep Dive
Concomitant use of pemigatinib (a CYP3A substrate) and a moderate or strong CYP3A inducer decreases pemigatinib exposure, which may reduce pemigatinib efficacy. When pemigatinib was coadministered with rifampin (a strong CYP3A inducer), the pemigatinib Cmax was decreased by 62% and AUC by 85%. Concomitant use with a moderate CYP3A inducer is predicted to decrease pemigatinib exposure by more than 50%. Concomitant use should be avoided1.
Why it happens (mechanism)
Induction of CYP3A-mediated pemigatinib metabolism
Literature reports
2 reports — tap to read
a) Concomitant use of pemigatinib and rifampin, a strong CYP3A inducer, decreased pemigatinib Cmax by 62% and AUC by 85% following a single oral dose of pemigatinib 13.5 mg 1.
b) Concomitant use of pemigatinib and a moderate CYP3A inducer is predicted to decrease pemigatinib exposure by more than 50% 1.
Common questions
Can I take Pemigatinib and Nafcillin Injection together?
Decreased pemigatinib exposure and risk of reduced efficacy Always confirm with your pharmacist or prescriber before making any change.
How serious is the Pemigatinib and Nafcillin 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 Pemigatinib or Nafcillin 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: PEMAZYRE(TM) oral tablets, pemigatinib oral tablets. Incyte Corporation (per FDA), Wilmington, DE, 2020. DailyMed
Keep reading about Pemigatinib
Keep reading about Nafcillin Injection
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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