Paroxetine and Phenelzine Interaction
Drug interaction information between Paroxetine and Phenelzine.
Paroxetine and Phenelzine have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Paroxetine and Phenelzine. Major interactions are generally avoided, moderate ones may need monitoring or a dose adjustment, and minor ones are usually low-risk. This page shows the documented mechanism and guidance. Label-documented interactions are not a complete safety review, so always confirm your own medications with a pharmacist or doctor. Educational information, not medical advice.
How They Interact
Taking these two drugs together can cause a dangerous buildup of brain chemicals that may lead to a severe reaction.
What To Do
Avoid this combination entirely as it can be very dangerous.
FDA Label Information
Examples selegiline, tranylcypromine, isocarboxazid, phenelzine, linezolid, methylene blue Pimozide and Thioridazine Clinical Impact Increased plasma concentrations of pimozide and thioridazine, drugs with a narrow therapeutic index, may increase the risk of QTc prolongation and ventricular arrhythmias.
Paroxetine Also Interacts With
- Linezolid major
- Pimozide major
- Thioridazine major
- Tranylcypromine moderate
- Selegiline moderate
Phenelzine Also Interacts With
- Sertraline moderate
- Fluoxetine moderate
- Citalopram moderate
- Venlafaxine moderate
- Fluvoxamine moderate
Frequently Asked Questions
Can I take Paroxetine and Phenelzine together?
This is a moderate interaction. Avoid this combination entirely as it can be very dangerous.
How serious is the interaction between Paroxetine and Phenelzine?
This interaction is classified as "moderate" severity by the FDA. Moderate interactions may worsen your condition or change how your medications work.
Why do Paroxetine and Phenelzine interact?
Taking these two drugs together can cause a dangerous buildup of brain chemicals that may lead to a severe reaction.
Understanding the Paroxetine and Phenelzine Interaction
FDA-approved prescribing information for these two drugs flags their combination as a moderate-severity interaction. Paroxetine belongs to the Selective Serotonin Reuptake Inhibitor (SSRI) class and Phenelzine belongs to the Monoamine Oxidase Inhibitor (MAOI) class - two categories that can collide when co-prescribed. The mechanism described in FDA labeling is: Taking these two drugs together can cause a dangerous buildup of brain chemicals that may lead to a severe reaction. Severity tiers matter: major flags generally advise avoidance, moderate flags often require monitoring or dose adjustment, and minor flags may only call for awareness.
Context around a specific patient determines real-world impact. Paroxetine has 51 total documented interactions on file in this dataset, and Phenelzine has 27. Each additional medication compounds the interaction surface, which is why pharmacists run full-profile checks rather than evaluating one pair at a time. FDA-derived guidance for this pair is: Avoid this combination entirely as it can be very dangerous. Timing of doses, renal and hepatic function, age, and other concurrent prescriptions all shape whether a labeled interaction matters clinically.
An interaction flag is not a verdict. A large share of labeled interactions are managed routinely in clinical practice, the fix may be as simple as spacing doses or adding a monitoring test. Others require the prescriber to choose a different medication entirely. This page surfaces FDA-sourced labeling and openFDA data for educational purposes only; it is not medical advice and cannot account for your full clinical picture. Never start, stop, or adjust either Paroxetine or Phenelzine based on a web page, speak with your prescriber or pharmacist before making any change.
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. Always consult your healthcare provider about drug interactions.
Read our methodology - how this data is sourced, computed, and verified.