Haloperidol and Fluoxetine Interaction

Drug interaction information between Haloperidol and Fluoxetine.

Haloperidol and Fluoxetine have a documented moderate interaction in FDA labeling.

FDA drug labeling documents a moderate-severity interaction between Haloperidol 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.

Drug A

Haloperidol

Typical Antipsychotic

Drug B

Fluoxetine

Selective Serotonin Reuptake Inhibitor (SSRI)

How They Interact

Fluoxetine slows down the process that clears haloperidol from your system. This can cause the level of the antipsychotic drug to rise in your blood.

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...

Frequently Asked Questions

What SPL severity band is on file for Haloperidol + Fluoxetine?

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 Haloperidol's 14. In the moderate band specifically: Haloperidol has 2 (also Tetrabenazine); Fluoxetine has 19 (also Alprazolam, Diazepam, Carbamazepine, Clozapine).

What mechanism field is on file for Haloperidol and Fluoxetine?

Fluoxetine slows down the process that clears haloperidol from your system. This can cause the level of the antipsychotic drug to rise in your blood.

Fluoxetine carries more major-labeled pairs than Haloperidol

SPL source-record counts only. This page's band is moderate · classes on file: Haloperidol (Typical Antipsychotic); Fluoxetine (Selective Serotonin Reuptake Inhibitor (SSRI)).

Fluoxetine has 6 major-labeled pairs vs Haloperidol's 0. This page itself is in the moderate band, not the major band.

Haloperidol

0 major · 2 moderate · 12 minor · 14 total

Fluoxetine

6 major · 19 moderate · 43 minor · 68 total

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.