Drug interactions
Ranolazine + Thioridazine
Severity: Contraindicated
Ranolazine and Thioridazine: 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
Ranolazine weakly inhibits CYP2D6, which may raise thioridazine levels, and both drugs prolong the QT interval. Thioridazine is contraindicated with QT-prolonging drugs because of the risk of torsades de pointes.
What this interaction means in plain words
Ranolazine and Thioridazine 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.
Ranolazine belongs to Cardiovascular; Thioridazine belongs to Central Nervous System.
Why it happens
Additive QT prolongation with ranolazine inhibition of CYP2D6-mediated thioridazine metabolism.
What to do
Avoid the combination and select an alternative antianginal or antipsychotic. ECG monitoring does not make it safe.
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
Other interactions of Thioridazine
- Abiraterone + Thioridazine Contraindicated
- Adagrasib + Thioridazine Contraindicated
- Amiodarone + Thioridazine Contraindicated
- Amisulpride + Thioridazine Contraindicated
- Amitriptyline + Thioridazine Contraindicated
- Amoxapine + Thioridazine Contraindicated
Frequently asked questions
Can I take Ranolazine with Thioridazine?
MediHelp rates the interaction as contraindicated. Ranolazine and Thioridazine 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. Ranolazine weakly inhibits CYP2D6, which may raise thioridazine levels, and both drugs prolong the QT interval. Thioridazine is contraindicated with QT-prolonging drugs because of the risk of torsades de pointes.
How serious is the interaction between Ranolazine and Thioridazine?
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 select an alternative antianginal or antipsychotic. ECG monitoring does not make it safe.
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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