Dofetilide and Darunavir: Interaction Details
AI-assisted, pharmacist-reviewed · Source data updated Aug 8, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Darunavir
No brand names on recordDofetilide
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
What happens
Increased antiarrhythmic exposure and an increased risk of antiarrhythmic-related adverse effects
Interaction Deep Dive
Coadministration of darunavir with drugs that are both antiarrhythmics and CYP3A substrates may increase the exposure of these drugs. When antiarrhythmics are coadministered with darunavir, therapeutic concentration monitoring, if available, is recommended123.
Why it happens (mechanism)
Inhibition of CYP3A-mediated metabolism by darunavir
Common questions
Can I take Dofetilide and Darunavir together?
Increased antiarrhythmic exposure and an increased risk of antiarrhythmic-related adverse effects Always confirm with your pharmacist or prescriber before making any change.
How serious is the Dofetilide and Darunavir interaction?
It is rated moderate. Can be significant — usually manageable with monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
From our Q&A
Real reader questions about these medications, each personally answered by our pharmacist:
Questions for your pharmacist
- Does my dose of Dofetilide or Darunavir need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there anything you'd monitor while I'm on both?
References (3)
- Product Information: PREZISTA(R) oral suspension, oral tablets, darunavir oral suspension, oral tablets. Janssen Products, LP (per FDA), Horsham, PA, 2023. DailyMed
- Product Information: PREZCOBIX® PED oral tablets for suspension, darunavir cobicistat oral tablets for suspension. Janssen Products, LP (per FDA), Horsham, PA, 2026. DailyMed
- Product Information: PREZCOBIX® oral tablets, darunavir cobicistat oral tablets. Janssen Products, LP (per FDA), Horsham, PA, 2026. DailyMed
Keep reading about Darunavir
Keep reading about Dofetilide
These medications also interact with supplements
Prescription drugs aren't the whole picture — herbal and dietary supplements can interact with them too. From the evidence-graded Natural Medicines database:
major · moderate · minor — check everything you take with our drug–supplement interaction checker.
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