Drug interactions
Phenobarbital + Ranolazine
Severity: Contraindicated
Phenobarbital and Ranolazine: contraindicated 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 is an enzyme inducer that can lower ranolazine exposure and weaken antianginal control. Ranolazine labeling contraindicates use with CYP3A inducers.
What this interaction means in plain words
Phenobarbital and Ranolazine are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two.
Why it happens
Induction of CYP3A4 by phenobarbital, increasing ranolazine clearance.
What to do
Avoid the combination and choose another antianginal. If phenobarbital is essential, use a non-ranolazine regimen for angina.
What to ask your pharmacist
- Is there an alternative to one of these two medicines for me?
- If both are essential, who is monitoring me and how often?
- Which symptoms mean I should stop and seek help straight away?
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Other interactions of Ranolazine
- Adagrasib + Ranolazine Contraindicated
- Amobarbital + Ranolazine Contraindicated
- Apalutamide + Ranolazine Contraindicated
- Butabarbital + Ranolazine Contraindicated
- Carbamazepine + Ranolazine Contraindicated
- Clarithromycin + Ranolazine Contraindicated
Frequently asked questions
Can I take Phenobarbital with Ranolazine?
MediHelp rates the interaction as contraindicated. Phenobarbital and Ranolazine are not normally used together. Taking them at the same time is expected to cause harm or make one of them unsafe, so a different medicine is usually chosen for one of the two. Phenobarbital is an enzyme inducer that can lower ranolazine exposure and weaken antianginal control. Ranolazine labeling contraindicates use with CYP3A inducers.
How serious is the interaction between Phenobarbital and Ranolazine?
MediHelp rates it contraindicated, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid the combination and choose another antianginal. If phenobarbital is essential, use a non-ranolazine regimen for angina.
What other medicines interact with Ranolazine?
MediHelp also lists interactions of Ranolazine with, for example, Adagrasib, Amobarbital, Apalutamide. The full list is on the Ranolazine page.
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