Drug interactions
Phenelzine + Trifluoperazine
Severity: Moderate
Phenelzine and Trifluoperazine: 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
Phenelzine with a phenothiazine antipsychotic may increase the risk of serotonin toxicity and neuroleptic malignant syndrome. Additive sedation and hypotension can also occur.
What this interaction means in plain words
Phenelzine and Trifluoperazine 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.
Why it happens
Additive effects of increased monoamine availability from MAO inhibition and D2 blockade, with additive hypotensive and sedative effects.
What to do
Use the lowest effective trifluoperazine dose with gradual titration. Monitor for hyperthermia, rigidity, clonus, mental status change and orthostatic hypotension.
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 Phenelzine
- 5-HTP + Phenelzine Contraindicated
- Amitriptyline + Phenelzine Contraindicated
- Amoxapine + Phenelzine Contraindicated
- Atomoxetine + Phenelzine Contraindicated
- Benzphetamine + Phenelzine Contraindicated
- Brimonidine + Phenelzine Contraindicated
Frequently asked questions
Can I take Phenelzine with Trifluoperazine?
MediHelp rates the interaction as moderate. Phenelzine and Trifluoperazine 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. Phenelzine with a phenothiazine antipsychotic may increase the risk of serotonin toxicity and neuroleptic malignant syndrome. Additive sedation and hypotension can also occur.
How serious is the interaction between Phenelzine and Trifluoperazine?
MediHelp rates it moderate, on a four-level scale (minor, moderate, major, contraindicated) based on published labels and references. What to do, in brief: Use the lowest effective trifluoperazine dose with gradual titration. Monitor for hyperthermia, rigidity, clonus, mental status change and orthostatic hypotension.
What other medicines interact with Phenelzine?
MediHelp also lists interactions of Phenelzine with, for example, 5-HTP, Amitriptyline, Amoxapine. The full list is on the Phenelzine page.
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