Drug interactions
Doxepin + Ranolazine
Severity: Moderate
Doxepin 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 doxepin can both prolong the QT interval. At higher doxepin doses the combination may increase arrhythmia risk, whereas low-dose doxepin has less effect.
What this interaction means in plain words
Doxepin 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.
Doxepin belongs to Dermatology; Ranolazine belongs to Cardiovascular.
Why it happens
Additive QT prolongation through effects on cardiac repolarisation.
What to do
Check a baseline ECG and correct potassium and magnesium. Use the lowest effective doxepin dose and repeat ECG if the dose rises.
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
Other interactions of Doxepin
- Doxepin + Isocarboxazid Contraindicated
- Doxepin + Phenelzine Contraindicated
- Doxepin + Procarbazine Contraindicated
- Doxepin + Safinamide Contraindicated
- Doxepin + Selegiline Contraindicated
- Doxepin + Tranylcypromine Contraindicated
Frequently asked questions
Can I take Doxepin with Ranolazine?
MediHelp rates the interaction as moderate. Doxepin 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 doxepin can both prolong the QT interval. At higher doxepin doses the combination may increase arrhythmia risk, whereas low-dose doxepin has less effect.
How serious is the interaction between Doxepin 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 correct potassium and magnesium. Use the lowest effective doxepin dose and repeat ECG if the dose rises.
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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