Venlafaxine and Fluoxetine Interaction
Drug interaction information between Venlafaxine and Fluoxetine.
Venlafaxine and Fluoxetine have a documented minor interaction in FDA labeling.
FDA drug labeling documents a minor-severity interaction between Venlafaxine and Fluoxetine. 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 drugs can affect a liver protein that helps the body process many types of medicine. This can lead to changes in how other drugs you take are broken down.
FDA Label Information
These findings have been confirmed in a clinical drug interaction study comparing the effect of venlafaxine to that of fluoxetine on the CYP2D6-mediated metabolism of dextromethorphan to dextrorphan.
Venlafaxine Also Interacts With
- Aspirin moderate
- Phenelzine moderate
- Metoprolol minor
- Alprazolam minor
- Warfarin minor
Fluoxetine Also Interacts With
- Aspirin major
- Warfarin major
- Olanzapine major
- Pimozide major
- Thioridazine major
Frequently Asked Questions
What SPL severity band is on file for Venlafaxine + Fluoxetine?
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?
Fluoxetine has 68 labeled pairs on file vs Venlafaxine's 22. In the minor band specifically: Venlafaxine has 20 (also Metoprolol, Alprazolam, Warfarin, Ketoconazole); Fluoxetine has 43 (also Ketoconazole, Lithium, Moxifloxacin, Erythromycin).
What mechanism field is on file for Venlafaxine and Fluoxetine?
These drugs can affect a liver protein that helps the body process many types of medicine. This can lead to changes in how other drugs you take are broken down.
Fluoxetine carries more major-labeled pairs than Venlafaxine
SPL source-record counts only. This page's band is minor · classes on file: Venlafaxine (Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)); Fluoxetine (Selective Serotonin Reuptake Inhibitor (SSRI)).
Fluoxetine has 6 major-labeled pairs vs Venlafaxine's 0. This page itself is in the minor band, not the major band.
0 major · 2 moderate · 20 minor · 22 total
- Other minor peers for Venlafaxine
- Metoprolol
- Alprazolam
- Warfarin
- Ketoconazole
6 major · 19 moderate · 43 minor · 68 total
- Other minor peers for Fluoxetine
- Ketoconazole
- Lithium
- Moxifloxacin
- Erythromycin
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.