Lamotrigine and Dofetilide Interaction
Drug interaction information between Lamotrigine and Dofetilide.
Lamotrigine and Dofetilide have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Lamotrigine and Dofetilide. 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.
How They Interact
Lamotrigine can change how the body handles dofetilide, a drug that can be dangerous if levels are slightly off.
What To Do
Using these two drugs together is not recommended.
FDA Label Information
Coadministration of lamotrigine with OCT2 substrates with a narrow therapeutic index (e.g., dofetilide) is not recommended.
Lamotrigine Also Interacts With
- Desmopressin moderate
- Valproate minor
- Carbamazepine minor
- Rifampin minor
- Phenytoin minor
Dofetilide Also Interacts With
- Bictegravir/Emtricitabine/Tenofovir major
- Dolutegravir major
- Dolutegravir/Lamivudine major
- Itraconazole major
- Clarithromycin moderate
Frequently Asked Questions
Can I take Lamotrigine and Dofetilide together?
This is a moderate interaction. Using these two drugs together is not recommended.
How serious is the interaction between Lamotrigine and Dofetilide?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Lamotrigine and Dofetilide interact?
Lamotrigine can change how the body handles dofetilide, a drug that can be dangerous if levels are slightly off.
Understanding the Lamotrigine and Dofetilide Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Lamotrigine belongs to the Anticonvulsant class and Dofetilide belongs to the Class III Antiarrhythmic class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Lamotrigine can change how the body handles dofetilide, a drug that can be dangerous if levels are slightly off. 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. Lamotrigine has 24 total documented interactions on file in this dataset, and Dofetilide has 8. 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: Using these two drugs together is not recommended. 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 Lamotrigine or Dofetilide 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.
Read our methodology - how this data is sourced, computed, and verified.