Dronedarone and Phenytoin Interaction
Drug interaction information between Dronedarone and Phenytoin.
Dronedarone and Phenytoin have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Dronedarone and Phenytoin. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Phenytoin causes your body to clear dronedarone out of your system too quickly, making the treatment less effective.
FDA Label Information
Rifampin and Other CYP3A Inducers Avoid rifampin or other CYP3A inducers such as phenobarbital, carbamazepine, phenytoin, and St.
Dronedarone Also Interacts With
- Ketoconazole major
- Clarithromycin major
- Voriconazole major
- Darunavir major
- Ezetimibe major
Phenytoin Also Interacts With
- Nirmatrelvir/Ritonavir major
- Posaconazole major
- Ranolazine major
- Voriconazole major
- Apixaban moderate
Frequently Asked Questions
What SPL severity band is on file for Dronedarone + Phenytoin?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Phenytoin has 147 labeled pairs on file vs Dronedarone's 22. In the moderate band specifically: Dronedarone has 5 (also Carbamazepine, Rifampin, Phenobarbital, Lovastatin); Phenytoin has 23 (also Apixaban, Aprepitant, Canagliflozin, Carbidopa/Levodopa).
What mechanism field is on file for Dronedarone and Phenytoin?
Phenytoin causes your body to clear dronedarone out of your system too quickly, making the treatment less effective.
Dronedarone carries more major-labeled pairs than Phenytoin
SPL source-record counts only. This page's band is moderate · classes on file: Dronedarone (Class III Antiarrhythmic); Phenytoin (Anticonvulsant (Hydantoin)).
Dronedarone has 9 major-labeled pairs vs Phenytoin's 4. This page itself is in the moderate band, not the major band.
9 major · 5 moderate · 8 minor · 22 total
- Other moderate peers for Dronedarone
- Carbamazepine
- Rifampin
- Phenobarbital
- Lovastatin
4 major · 23 moderate · 120 minor · 147 total
- Other moderate peers for Phenytoin
- Apixaban
- Aprepitant
- Canagliflozin
- Carbidopa/Levodopa
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.