Morphine and Mirtazapine Interaction
Drug interaction information between Morphine and Mirtazapine.
Morphine and Mirtazapine have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Morphine and Mirtazapine. 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
These medications both change how serotonin works in your nervous system. Using them at the same time can cause too much serotonin to build up.
FDA Label Information
Examples: Selective serotonin reuptake inhibitors (SSRIs), serotonin and norepinephrine reuptake inhibitors (SNRIs), tricyclic antidepressants (TCAs), triptans, 5-HT3 receptor antagonists, drugs that effect the serotonin neurotransmitter system (e.g., mirtazapine, trazodone, tramadol), certain muscle relaxants (i.e., cyclobenzaprine, metaxalone), monoamine oxidase (MAO) inhibitors (those intended to treat psychiatric disorders and also others, such as linezolid and intravenous methylene blue).
Morphine Also Interacts With
- Trazodone minor
- Tramadol minor
- Cyclobenzaprine minor
- Verapamil minor
- Linezolid minor
Mirtazapine Also Interacts With
- Linezolid major
- Alprazolam moderate
- Diazepam moderate
- Phenelzine moderate
- Tranylcypromine moderate
Frequently Asked Questions
What SPL severity band is on file for Morphine + Mirtazapine?
Compiled FDA labeling labels this pair minor. That is a source-record field, not an individual medication-combination decision.
Which drug in this pair has the larger labeled-interaction portfolio?
Morphine has 30 labeled pairs on file vs Mirtazapine's 29. In the minor band specifically: Morphine has 30 (also Trazodone, Tramadol, Cyclobenzaprine, Verapamil); Mirtazapine has 23 (also Buspirone, Warfarin, Carbamazepine, Lithium).
What mechanism field is on file for Morphine and Mirtazapine?
These medications both change how serotonin works in your nervous system. Using them at the same time can cause too much serotonin to build up.
Mirtazapine carries more major-labeled pairs than Morphine
SPL source-record counts only. This page's band is minor · classes on file: Morphine (Opioid Analgesic); Mirtazapine (Noradrenergic and Specific Serotonergic Antidepressant (NaSSA)).
Mirtazapine has 1 major-labeled pair vs Morphine's 0. This page itself is in the minor band, not the major band.
0 major · 0 moderate · 30 minor · 30 total
- Other minor peers for Morphine
- Trazodone
- Tramadol
- Cyclobenzaprine
- Verapamil
1 major · 5 moderate · 23 minor · 29 total
- Other minor peers for Mirtazapine
- Buspirone
- Warfarin
- Carbamazepine
- Lithium
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.