Drug interactions
Amiodarone + Phenobarbital
Severity: Moderate
Amiodarone and Phenobarbital: moderate interaction.
Last updated
For healthcare professionals — reference only. This page is a brief summary, not medical advice and not a substitute for official labeling or clinical judgement. Always verify before prescribing or dispensing.
Summary
Phenobarbital induces CYP3A4 and other enzymes and may reduce amiodarone exposure, risking loss of rhythm control. Amiodarone may also raise levels of some antiepileptics, complicating management.
What this interaction means in plain words
Amiodarone and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken.
Why it happens
Phenobarbital induction of CYP3A4 increases amiodarone clearance.
What to do
Monitor arrhythmia control and consider amiodarone level measurement with dose adjustment. Monitor phenobarbital levels and sedation when starting or stopping amiodarone.
What to ask your pharmacist
- Should I take them at different times of day?
- Does the dose of either medicine need to change?
- Is there anything I should avoid, such as alcohol or certain foods, while on both?
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Other interactions of Amiodarone
- Amiodarone + Amisulpride Contraindicated
- Amiodarone + Arsenic trioxide Contraindicated
- Amiodarone + Dofetilide Contraindicated
- Amiodarone + Dronedarone Contraindicated
- Amiodarone + Droperidol Contraindicated
- Amiodarone + Eliglustat Contraindicated
Frequently asked questions
Can I take Amiodarone with Phenobarbital?
MediHelp rates the interaction as moderate. Amiodarone and Phenobarbital can affect each other. The combination is often manageable, but it may need a change of dose, a change of timing, or extra checks while both are taken. Phenobarbital induces CYP3A4 and other enzymes and may reduce amiodarone exposure, risking loss of rhythm control. Amiodarone may also raise levels of some antiepileptics, complicating management.
How serious is the interaction between Amiodarone and Phenobarbital?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Monitor arrhythmia control and consider amiodarone level measurement with dose adjustment. Monitor phenobarbital levels and sedation when starting or stopping amiodarone.
What other medicines interact with Amiodarone?
MediHelp also lists interactions of Amiodarone with, for example, Amisulpride, Arsenic trioxide, Dofetilide. The full list is on the Amiodarone page.
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