Drug interactions
Posaconazole + Quercetin
Severity: Minor
Posaconazole and Quercetin: minor interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Quercetin supplements might reduce posaconazole absorption by affecting intestinal efflux, though the direction and magnitude of effect are uncertain. Any clinical impact is likely small.
What this interaction means in plain words
Posaconazole and Quercetin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised.
Why it happens
Quercetin modulates P-glycoprotein activity, but the effect on posaconazole is not well established.
What to do
Advise patients to avoid high-dose quercetin supplements during antifungal therapy, and check posaconazole levels if response is inadequate.
What to ask your pharmacist
- Is there anything I should notice while taking both?
- Do I need to tell my doctor at the next visit?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Posaconazole and Quercetin, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 7 days on the web. No card needed.
Other interactions of Posaconazole
- Artemether + Posaconazole Contraindicated
- Avanafil + Posaconazole Contraindicated
- Cobimetinib + Posaconazole Contraindicated
- Conivaptan + Posaconazole Contraindicated
- Dihydroergotamine intranasal + Posaconazole Contraindicated
- Dihydroergotamine + Posaconazole Contraindicated
Frequently asked questions
Can I take Posaconazole with Quercetin?
MediHelp rates the interaction as minor. Posaconazole and Quercetin have a small, usually unimportant interaction. Most people can take both; the pharmacist may still mention it so that any unexpected effect is recognised. Quercetin supplements might reduce posaconazole absorption by affecting intestinal efflux, though the direction and magnitude of effect are uncertain. Any clinical impact is likely small.
How serious is the interaction between Posaconazole and Quercetin?
MediHelp rates it minor, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Advise patients to avoid high-dose quercetin supplements during antifungal therapy, and check posaconazole levels if response is inadequate.
What other medicines interact with Posaconazole?
MediHelp also lists interactions of Posaconazole with, for example, Artemether, Avanafil, Cobimetinib. The full list is on the Posaconazole page.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
