Drug interactions
Olanzapine + Trazodone
Severity: Moderate
Olanzapine and Trazodone: 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
Both agents can prolong the QT interval, so the combination may increase the risk of ventricular arrhythmia. Risk is higher with existing cardiac disease, electrolyte imbalance or other QT-prolonging drugs.
What this interaction means in plain words
Olanzapine and Trazodone 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.
Olanzapine belongs to Central Nervous System; Trazodone belongs to Central Nervous System.
Why it happens
Additive pharmacodynamic QT prolongation through cardiac potassium channel effects.
What to do
Check ECG and electrolytes at baseline and after dose changes. Use the lowest effective doses and avoid adding further QT-prolonging drugs.
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 Trazodone
- Arsenic trioxide + Trazodone Contraindicated
- Ibutilide + Trazodone Contraindicated
- Isocarboxazid + Trazodone Contraindicated
- Levoketoconazole + Trazodone Contraindicated
- Methylene blue + Trazodone Contraindicated
- Phenelzine + Trazodone Contraindicated
Other interactions of Olanzapine
Frequently asked questions
Can I take Olanzapine with Trazodone?
MediHelp rates the interaction as moderate. Olanzapine and Trazodone 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. Both agents can prolong the QT interval, so the combination may increase the risk of ventricular arrhythmia. Risk is higher with existing cardiac disease, electrolyte imbalance or other QT-prolonging drugs.
How serious is the interaction between Olanzapine and Trazodone?
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 ECG and electrolytes at baseline and after dose changes. Use the lowest effective doses and avoid adding further QT-prolonging drugs.
What other medicines interact with Trazodone?
MediHelp also lists interactions of Trazodone with, for example, Arsenic trioxide, Ibutilide, Isocarboxazid. The full list is on the Trazodone page.
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