Drug interactions
Haloperidol + Trifluoperazine
Severity: Major
Haloperidol and Trifluoperazine: 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 are antipsychotics with QT-prolonging potential, and combined use increases the risk of arrhythmia including torsades de pointes. Additive extrapyramidal effects, sedation and neuroleptic malignant syndrome risk also apply.
What this interaction means in plain words
Haloperidol and Trifluoperazine 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
Additive QTc prolongation and additive dopamine D2 receptor antagonism.
What to do
Avoid combining two antipsychotics unless clearly justified; use a single agent where possible. If both are needed, monitor ECG, electrolytes and extrapyramidal symptoms.
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 Haloperidol
- Dofetilide + Haloperidol Contraindicated
- Dronedarone + Haloperidol Contraindicated
- Haloperidol + Ibutilide Contraindicated
- Haloperidol + Levoketoconazole Contraindicated
- Haloperidol + Panobinostat Contraindicated
- Haloperidol + Pimozide Contraindicated
Frequently asked questions
Can I take Haloperidol with Trifluoperazine?
MediHelp rates the interaction as major. Haloperidol and Trifluoperazine 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 are antipsychotics with QT-prolonging potential, and combined use increases the risk of arrhythmia including torsades de pointes. Additive extrapyramidal effects, sedation and neuroleptic malignant syndrome risk also apply.
How serious is the interaction between Haloperidol and Trifluoperazine?
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 two antipsychotics unless clearly justified; use a single agent where possible. If both are needed, monitor ECG, electrolytes and extrapyramidal symptoms.
What other medicines interact with Haloperidol?
MediHelp also lists interactions of Haloperidol with, for example, Dofetilide, Dronedarone, Ibutilide. The full list is on the Haloperidol page.
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