Drug interactions
Doxepin + Trazodone
Severity: Major
Doxepin and Trazodone: major interaction.
Last updated Sources: US FDA label
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 drugs can prolong the QT interval and increase serotonergic activity, and both are sedating. Combined use raises the risk of arrhythmia, serotonin syndrome, excessive sedation and orthostatic hypotension.
What this interaction means in plain words
Doxepin and Trazodone can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for.
Doxepin belongs to Dermatology; Trazodone belongs to Central Nervous System.
Why it happens
Additive QT prolongation, serotonergic effects and CNS depression.
What to do
Avoid using both together when possible. If combined, use low doses, monitor the ECG, and watch for signs of serotonin toxicity and oversedation.
What to ask your pharmacist
- Does the benefit of taking both outweigh the risk in my case?
- Do I need any blood test, ECG or other check while on both?
- What early warning signs should I watch for, and what should I do if they appear?
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References
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 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 Trazodone?
MediHelp rates the interaction as major. Doxepin and Trazodone can interact in a way that may be serious. Using them together is sometimes necessary, but it needs a deliberate decision by the prescriber, a plan for monitoring, and clear advice on the warning signs to watch for. Both drugs can prolong the QT interval and increase serotonergic activity, and both are sedating. Combined use raises the risk of arrhythmia, serotonin syndrome, excessive sedation and orthostatic hypotension.
How serious is the interaction between Doxepin and Trazodone?
MediHelp rates it major, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Avoid using both together when possible. If combined, use low doses, monitor the ECG, and watch for signs of serotonin toxicity and oversedation.
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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