Abrocitinib and Posaconazole: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 11, 2026 · Source data updated Jul 10, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Posaconazole
Abrocitinib
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.
You've been prescribed posaconazole (an antifungal medicine) along with abrocitinib (Cibinqo, used for eczema). Abrocitinib may block a protein pump in your body called P-gp that normally helps move posaconazole along. When that pump is slowed, more posaconazole can build up in your system, which could make its side effects (like nausea, headache, or changes in liver tests) more likely.
I want to reassure you that this concern is based on how the drugs work in theory, not on strong real-world reports. Your care team can manage it easily by watching how you feel and adjusting things if needed. Please don't stop either medicine on your own, just check in with your pharmacist or doctor.
Effect: Increased posaconazole exposure when co-administered with abrocitinib.
Mechanism: Abrocitinib may inhibit P-gp-mediated efflux of posaconazole, reducing clearance and raising systemic exposure (AUC/Cmax). Neither agent is activated by this pathway, so the direction is a straightforward increase in posaconazole levels.
Evidence: Theoretical; magnitude and onset not quantified.
- Monitor for posaconazole-related adverse effects (GI upset, hepatotoxicity, QTc prolongation).
- Consider LFTs and ECG per clinical context.
- Posaconazole dose may need individualization; no fixed adjustment is defined.
Rated major given posaconazole's exposure-dependent toxicity potential.
What happens
Increased posaconazole exposure
Interaction Deep Dive
Using posaconazole together with P-gp inhibitors, since this combination can raise posaconazole exposure123.
Why it happens (mechanism)
Inhibition of P-gp-mediated efflux transport of posaconazole
How to manage this interaction
Here's how a care team typically handles this combination:
- Keep taking both medicines as prescribed unless your doctor or pharmacist tells you otherwise.
- Your team may monitor you more closely for posaconazole side effects such as stomach upset, headache, or changes in liver tests.
- Your posaconazole dose may be adjusted and individualized by your care team if needed.
Let your pharmacist or prescriber know if you notice new nausea, vomiting, unusual tiredness, yellowing of the skin or eyes, or a racing or irregular heartbeat. These are easy to check on, and your team can tailor your treatment to keep you safe.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Abrocitinib and Posaconazole together?
Abrocitinib may raise posaconazole levels by slowing its removal, so your care team may monitor you more closely and adjust the posaconazole dose if needed. Keep taking both as prescribed and report any new side effects. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Abrocitinib and Posaconazole 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 is the Abrocitinib and Posaconazole interaction managed?
Here's how a care team typically handles this combination: Keep taking both medicines as prescribed unless your doctor or pharmacist tells you otherwise. Your team may monitor you more closely for posaconazole side effects such as stomach upset, headache, or changes in liver tests. Your posaconazole dose may be adjusted and individualized by your care team if needed. Let your pharmacist or prescri… Management is individual — always follow your own care team's guidance.
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 Abrocitinib or Posaconazole 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 (3)
- Product Information: NOXAFIL® PowderMix delayed-release oral suspension, posaconazole delayed-release oral suspension. Merck Sharp & Dohme LLC (per FDA), Rahway, NJ, 2026. DailyMed
- Product Information: NOXAFIL® intravenous injection, oral delayed-release tablets, oral suspension, posaconazole intravenous injection, oral delayed-release tablets, oral suspension. Merck Sharp & Dohme LLC (per FDA), Rahway, NJ, 2026. DailyMed
- Product Information: Posaconazole oral delayed-release tablets, posaconazole oral delayed-release tablets. SpecGx LLC (per DailyMed), Webster Groves, MO, 2024. DailyMed
Keep reading about Posaconazole
Keep reading about Abrocitinib
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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