Drug interactions
Nefazodone + Trazodone
Severity: Major
Nefazodone and Trazodone: major 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
Nefazodone strongly inhibits CYP3A4, raising trazodone levels, and both drugs are serotonergic. Excess trazodone exposure can cause sedation, hypotension and serotonin syndrome.
What this interaction means in plain words
Nefazodone 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.
Why it happens
CYP3A4 inhibition of trazodone metabolism by nefazodone, plus additive serotonergic effects.
What to do
Avoid combining these antidepressants; if switching, allow washout or cross-taper with a reduced trazodone dose. Monitor for sedation, hypotension and serotonin toxicity.
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?
Pro+ members
Unlock the full page
Create an account and start a Pro+ trial to unlock the full management advice for Nefazodone and Trazodone, the additional notes, the evidence detail and the whole-prescription interaction checker.
- Full clinical management advice
- Additional notes
- Evidence detail
- Interaction checker for a whole prescription
Try Pro+ free for 14 days on the web. No card needed.
Other interactions of Trazodone
- Arsenic trioxide + Trazodone Contraindicated
- Ibutilide + Trazodone Contraindicated
- Isocarboxazid + Trazodone Contraindicated
- Levoketoconazole + Trazodone Contraindicated
- Methylene blue + Trazodone Contraindicated
- Phenelzine + Trazodone Contraindicated
Frequently asked questions
Can I take Nefazodone with Trazodone?
MediHelp rates the interaction as major. Nefazodone 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. Nefazodone strongly inhibits CYP3A4, raising trazodone levels, and both drugs are serotonergic. Excess trazodone exposure can cause sedation, hypotension and serotonin syndrome.
How serious is the interaction between Nefazodone 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 combining these antidepressants; if switching, allow washout or cross-taper with a reduced trazodone dose. Monitor for sedation, hypotension and serotonin toxicity.
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.
Full monographs, dosing and an interaction checker in the MediHelp app
Open the complete reference, check multi-drug interactions and use dosing tools in the MediHelp app.
