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Dofetilide and Itraconazole Interaction

Drug interaction information between Dofetilide and Itraconazole.

Dofetilide and Itraconazole have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Dofetilide and Itraconazole. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.

Drug A

Dofetilide

Class III Antiarrhythmic

Drug B

Itraconazole

Azole Antifungal

How They Interact

Itraconazole interferes with the way your body breaks down dofetilide, potentially causing the heart medication to reach dangerous levels.

What To Do

Avoid taking these two medicines together and wait two weeks after stopping itraconazole before starting dofetilide.

FDA Label Information

Antiarrhythmics Disopyramide Dofetilide Dronedarone Quinidine a Contraindicated during and 2 weeks after itraconazole treatment.

Frequently Asked Questions

Can I take Dofetilide and Itraconazole together?

This is a major interaction. Avoid taking these two medicines together and wait two weeks after stopping itraconazole before starting dofetilide.

How serious is the interaction between Dofetilide and Itraconazole?

This interaction is classified as "major" severity by the FDA. Major interactions may be life-threatening or cause serious side effects.

Why do Dofetilide and Itraconazole interact?

Itraconazole interferes with the way your body breaks down dofetilide, potentially causing the heart medication to reach dangerous levels.

Understanding the Dofetilide and Itraconazole Interaction

FDA-approved prescribing information for these two drugs flags their combination as a major-severity interaction. Dofetilide belongs to the Class III Antiarrhythmic class and Itraconazole belongs to the Azole Antifungal class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Itraconazole interferes with the way your body breaks down dofetilide, potentially causing the heart medication to reach dangerous levels. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.

Context around a specific patient determines real-world impact. Dofetilide has 8 total documented interactions on file in this dataset, and Itraconazole has 116. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Avoid taking these two medicines together and wait two weeks after stopping itraconazole before starting dofetilide. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.

An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Dofetilide or Itraconazole based on a web page, speak with your prescriber or pharmacist before making any change.

Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.