Does Itraconazole Interact With Phenytoin?

Anticonvulsants Phenobarbital Phenytoin a Not recommended 2 weeks before and during itraconazole treatment.

Severity: Major

Severity basis: drug interactions section (keywords: not recommended). Combining Itraconazole (Azole antifungal (strong CYP3A4 inhibitor)) and Phenytoin (Anticonvulsant) is classified as a major interaction.

What to Do

The label advises avoiding this combination or using it only under close medical supervision. Talk to your prescriber or pharmacist before combining them.

From the FDA Label

Anticonvulsants Phenobarbital Phenytoin a Not recommended 2 weeks before and during itraconazole treatment.

Source: FDA structured product labeling (set_id 23126370-8d6a-4027-bd8f-860e2776ba3a).

Itraconazole

Azole antifungal (strong CYP3A4 inhibitor)

Brands: Sporanox, Tolsura

View Itraconazole safety profile

Phenytoin

Anticonvulsant

Brands: Dilantin

View Phenytoin safety profile

Check these against your full medication list in our free Interaction Checker

This information is educational — not medical advice.

This page is provided for general educational purposes and summarizes publicly available data from sources such as the U.S. Food & Drug Administration. It is not a substitute for the judgment of a licensed clinician and should not be used to start, stop, or change any medication. It may be incomplete or out of date, and individual circumstances vary. Always talk with your prescriber or pharmacist about your specific medications and health conditions. If you think you may have a medical emergency, call 911.

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