Drug interactions
Perphenazine + Trazodone
Severity: Major
Perphenazine 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
Both drugs can prolong the QT interval, so combined use may increase the likelihood of torsades de pointes. Perphenazine is also a CYP2D6 substrate and trazodone may add sedation and hypotension.
What this interaction means in plain words
Perphenazine 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.
Perphenazine belongs to Central Nervous System; Trazodone belongs to Central Nervous System.
Why it happens
Additive pharmacodynamic QT prolongation; additive sedative and hypotensive effects.
What to do
Avoid if a safer alternative exists; otherwise obtain baseline and follow-up ECGs and correct electrolytes. Use the lowest effective doses and monitor for syncope or palpitations.
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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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 Perphenazine
- Ibutilide + Perphenazine Contraindicated
- Perphenazine + Pimozide Contraindicated
- Perphenazine + Thioridazine Contraindicated
- Adagrasib + Perphenazine Major
- Alfentanil + Perphenazine Major
- Amiodarone + Perphenazine Major
Frequently asked questions
Can I take Perphenazine with Trazodone?
MediHelp rates the interaction as major. Perphenazine 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, so combined use may increase the likelihood of torsades de pointes. Perphenazine is also a CYP2D6 substrate and trazodone may add sedation and hypotension.
How serious is the interaction between Perphenazine 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 if a safer alternative exists; otherwise obtain baseline and follow-up ECGs and correct electrolytes. Use the lowest effective doses and monitor for syncope or palpitations.
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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