Mirtazapine and Phenelzine Interaction
Drug interaction information between Mirtazapine and Phenelzine.
Mirtazapine and Phenelzine have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Mirtazapine and Phenelzine. This page displays the available source-record category and label text. The category is not an individual risk estimate or medication-combination direction.
How They Interact
Both of these medicines increase the level of a brain chemical called serotonin. Taking them together can cause serotonin to reach dangerous levels in the body.
FDA Label Information
Examples selegiline, tranylcypromine, isocarboxazid, phenelzine, linezolid, methylene blue Other Serotonergic Drugs Clinical Impact The concomitant use of serotonergic drugs with mirtazapine increases the risk of serotonin syndrome.
Mirtazapine Also Interacts With
- Linezolid major
- Alprazolam moderate
- Diazepam moderate
- Tranylcypromine moderate
- Selegiline moderate
Phenelzine Also Interacts With
- Sertraline moderate
- Fluoxetine moderate
- Citalopram moderate
- Venlafaxine moderate
- Fluvoxamine moderate
Frequently Asked Questions
What SPL severity band is on file for Mirtazapine + Phenelzine?
Compiled FDA labeling labels this pair moderate. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Mirtazapine has 29 labeled pairs on file vs Phenelzine's 27. In the moderate band specifically: Mirtazapine has 5 (also Alprazolam, Diazepam, Tranylcypromine, Selegiline); Phenelzine has 11 (also Sertraline, Fluoxetine, Citalopram, Venlafaxine).
What mechanism field is on file for Mirtazapine and Phenelzine?
Both of these medicines increase the level of a brain chemical called serotonin. Taking them together can cause serotonin to reach dangerous levels in the body.
Mirtazapine carries more major-labeled pairs than Phenelzine
SPL source-record counts only. This page's band is moderate · classes on file: Mirtazapine (Noradrenergic and Specific Serotonergic Antidepressant (NaSSA)); Phenelzine (Monoamine Oxidase Inhibitor (MAOI)).
Mirtazapine has 1 major-labeled pair vs Phenelzine's 0. This page itself is in the moderate band, not the major band.
1 major · 5 moderate · 23 minor · 29 total
- Other moderate peers for Mirtazapine
- Alprazolam
- Diazepam
- Tranylcypromine
- Selegiline
0 major · 11 moderate · 16 minor · 27 total
- Other moderate peers for Phenelzine
- Sertraline
- Fluoxetine
- Citalopram
- Venlafaxine
Sources: FDA Drug Labels (SPL) via openFDA (2026). This is for informational purposes only and is not medical advice. This registry does not provide individual medication-combination directions.
Read our methodology - how this data is sourced, computed, and verified.