Fluoxetine and Clozapine Interaction
Drug interaction information between Fluoxetine and Clozapine.
Fluoxetine and Clozapine have a documented moderate interaction in FDA labeling.
FDA drug labeling documents a moderate-severity interaction between Fluoxetine and Clozapine. 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
Fluoxetine prevents your body from processing clozapine correctly, leading to higher levels of the drug. This increases the risk of experiencing dangerous side effects.
FDA Label Information
Monoamine Oxidase Inhibitors (MAOIs): ( 2.9 , 2.10 , 4.1 , 5.2 ) Drugs Metabolized by CYP2D6: Fluoxetine is a potent inhibitor of CYP2D6 enzyme pathway ( 7.7 ) Tricyclic Antidepressants (TCAs): Monitor TCA levels during coadministration with fluoxetine or when fluoxetine has been recently discontinued ( 5.2 , 7.7 ) CNS Acting Drugs: Caution should be used when taken in combination with other centrally acting drugs ( 7.2 ) Benzodiazepines: Diazepam – increased t½, alprazolam - further psychomotor performance decrement due to increased levels ( 7.7 ) Antipsychotics: Potential for elevation...
Fluoxetine Also Interacts With
- Aspirin major
- Warfarin major
- Olanzapine major
- Pimozide major
- Thioridazine major
Clozapine Also Interacts With
- Cyclobenzaprine moderate
- Diphenhydramine moderate
- Sertraline minor
- Escitalopram minor
- Bupropion minor
Frequently Asked Questions
What SPL severity band is on file for Fluoxetine + Clozapine?
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?
Fluoxetine has 68 labeled pairs on file vs Clozapine's 42. In the moderate band specifically: Fluoxetine has 19 (also Alprazolam, Diazepam, Carbamazepine, Haloperidol); Clozapine has 3 (also Cyclobenzaprine, Diphenhydramine).
What mechanism field is on file for Fluoxetine and Clozapine?
Fluoxetine prevents your body from processing clozapine correctly, leading to higher levels of the drug. This increases the risk of experiencing dangerous side effects.
Fluoxetine carries more major-labeled pairs than Clozapine
SPL source-record counts only. This page's band is moderate · classes on file: Fluoxetine (Selective Serotonin Reuptake Inhibitor (SSRI)); Clozapine (Atypical Antipsychotic).
Fluoxetine has 6 major-labeled pairs vs Clozapine's 0. This page itself is in the moderate band, not the major band.
6 major · 19 moderate · 43 minor · 68 total
- Other moderate peers for Fluoxetine
- Alprazolam
- Diazepam
- Carbamazepine
- Haloperidol
0 major · 3 moderate · 39 minor · 42 total
- Other moderate peers for Clozapine
- Cyclobenzaprine
- Diphenhydramine
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.