Drug interactions
Protriptyline + Ranolazine
Severity: Moderate
Protriptyline and Ranolazine: 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
Ranolazine and the tricyclic antidepressant protriptyline each can lengthen the QT interval, so combined use may raise the risk of ventricular arrhythmias including torsades de pointes. Risk is greater with electrolyte disturbance, bradycardia or underlying cardiac disease.
What this interaction means in plain words
Protriptyline and Ranolazine 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
Additive pharmacodynamic QTc prolongation; ranolazine also inhibits CYP2D6, which may modestly raise protriptyline exposure.
What to do
Check a baseline ECG and follow the QTc after starting the combination, and correct potassium and magnesium. Use the lowest effective ranolazine dose and consider another antidepressant if the QTc lengthens substantially.
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 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 Protriptyline with Ranolazine?
MediHelp rates the interaction as moderate. Protriptyline and Ranolazine 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. Ranolazine and the tricyclic antidepressant protriptyline each can lengthen the QT interval, so combined use may raise the risk of ventricular arrhythmias including torsades de pointes. Risk is greater with electrolyte disturbance, bradycardia or underlying cardiac disease.
How serious is the interaction between Protriptyline and Ranolazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Check a baseline ECG and follow the QTc after starting the combination, and correct potassium and magnesium. Use the lowest effective ranolazine dose and consider another antidepressant if the QTc lengthens substantially.
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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