Daridorexant and Nafcillin Injection: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Daridorexant
No brand names on recordNafcillin 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
Reduced daridorexant exposure and reduced efficacy of daridorexant
Interaction Deep Dive
Avoid concomitant use of daridorexant with a strong or moderate CYP3A4 inducer. Coadministration of daridorexant (CYP3A4 substrate) with a moderate or strong CYP3A4 inducer reduces exposure to daridorexant, which may reduce the efficacy of daridorexant. Concomitant use of daridorexant and rifAMPin decreased daridorexant AUC by more than 50% and concomitant use of efavirenz decreased daridorexant AUC and Cmax1.
Why it happens (mechanism)
Induction of CYP3A4-mediated metabolism of daridorexant
Literature reports
2 reports — tap to read
a) In a population-based pharmacokinetic analysis, concomitant use of daridorexant and rifAMPin (strong CYP3A4 inducer) decreased daridorexant AUC by more than 50% 1.
b) Concomitant use of daridorexant 50 mg and efavirenz (moderate CYP3A4 inducer) 600 mg decreased daridorexant AUC by a geometric mean ratio (GMR) of 0.4 (90% CI, 0.3 to 0.4) and Cmax by a GMR of 0.6 (90% CI, 0.5 to 0.8) 1.
Common questions
Can I take Daridorexant and Nafcillin Injection together?
Reduced daridorexant exposure and reduced efficacy of daridorexant Always confirm with your pharmacist or prescriber before making any change.
How serious is the Daridorexant 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 "probable". Good supporting evidence, though not definitively proven.
Questions for your pharmacist
- Does my dose of Daridorexant 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: QUVIVIQ(R) oral tablets, daridorexant oral tablets. Idorsia Pharmaceuticals US Inc (per FDA), Radnor, PA, 2023. DailyMed
Keep reading about Daridorexant
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.
Check another combination
Our instant two-drug interaction checker is almost here.
Still have questions about this combination?
Every question gets a real answer from a licensed pharmacist — free, and usually within a day.
Ask the pharmacist