Drug interactions
Atazanavir + Voriconazole
Severity: Major
Atazanavir and Voriconazole: major interaction.
Last updated Sources: US FDA label
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
Voriconazole and atazanavir are both CYP3A4 substrates and inhibitors, so each may raise the other's exposure. Boosted atazanavir regimens containing ritonavir may also lower voriconazole levels through CYP2C19 induction, making the net effect unpredictable. Both drugs can cause QT/PR prolongation and hyperbilirubinemia or hepatotoxicity.
What this interaction means in plain words
Atazanavir and Voriconazole 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.
Atazanavir belongs to Anti Virals; Voriconazole belongs to Anti Fungals.
Why it happens
Mutual inhibition of CYP3A4-mediated metabolism, with possible ritonavir-driven induction of voriconazole clearance via CYP2C19.
What to do
Avoid the combination where an alternative exists; if used, monitor voriconazole trough concentrations, ECG (QTc, PR interval) and liver function. Adjust doses according to drug levels and tolerability.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Atazanavir and Voriconazole, 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.
References
Other interactions of Voriconazole
- Avanafil + Voriconazole Contraindicated
- Butabarbital + Voriconazole Contraindicated
- Carbamazepine + Voriconazole Contraindicated
- Conivaptan + Voriconazole Contraindicated
- Dihydroergotamine intranasal + Voriconazole Contraindicated
- Dihydroergotamine + Voriconazole Contraindicated
Other interactions of Atazanavir
- Alfuzosin + Atazanavir Contraindicated
- Atazanavir + Avanafil Contraindicated
- Atazanavir + Dronedarone Contraindicated
- Atazanavir + Eletriptan Contraindicated
- Atazanavir + Eplerenone Contraindicated
- Atazanavir + Ergotamine Contraindicated
Frequently asked questions
Can I take Atazanavir with Voriconazole?
MediHelp rates the interaction as major. Atazanavir and Voriconazole 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. Voriconazole and atazanavir are both CYP3A4 substrates and inhibitors, so each may raise the other's exposure. Boosted atazanavir regimens containing ritonavir may also lower voriconazole levels through CYP2C19 induction, making the net effect unpredictable. Both drugs can cause QT/PR prolongation and hyperbilirubinemia or hepatotoxicity.
How serious is the interaction between Atazanavir and Voriconazole?
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 the combination where an alternative exists; if used, monitor voriconazole trough concentrations, ECG (QTc, PR interval) and liver function. Adjust doses according to drug levels and tolerability.
What other medicines interact with Voriconazole?
MediHelp also lists interactions of Voriconazole with, for example, Avanafil, Butabarbital, Carbamazepine. The full list is on the Voriconazole 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.
