Drug interactions
Itraconazole + Posaconazole
Severity: Major
Itraconazole and Posaconazole: major 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
Both azoles can prolong the QTc interval, so combining them adds to arrhythmia risk. There is also little reason to give two azole antifungals together, and they may affect each other's exposure.
What this interaction means in plain words
Itraconazole and Posaconazole can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Itraconazole belongs to Anti Fungals; Posaconazole belongs to Anti Fungals.
Why it happens
Additive QT prolongation, with mutual inhibition of CYP3A4 and P-glycoprotein.
What to do
Avoid concurrent use unless clearly justified. If unavoidable, monitor ECG and electrolytes, and consider azole levels.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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Other interactions of Itraconazole
- Alfuzosin + Itraconazole Contraindicated
- Alprazolam + Itraconazole Contraindicated
- Avanafil + Itraconazole Contraindicated
- Conivaptan + Itraconazole Contraindicated
- Dihydroergotamine intranasal + Itraconazole Contraindicated
- Dihydroergotamine + Itraconazole Contraindicated
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 Itraconazole with Posaconazole?
MediHelp rates the interaction as major. Itraconazole and Posaconazole can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Both azoles can prolong the QTc interval, so combining them adds to arrhythmia risk. There is also little reason to give two azole antifungals together, and they may affect each other's exposure.
How serious is the interaction between Itraconazole and Posaconazole?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid concurrent use unless clearly justified. If unavoidable, monitor ECG and electrolytes, and consider azole levels.
What other medicines interact with Itraconazole?
MediHelp also lists interactions of Itraconazole with, for example, Alfuzosin, Alprazolam, Avanafil. The full list is on the Itraconazole page.
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