Fluoxetine and Pimozide Interaction

Drug interaction information between Fluoxetine and Pimozide.

Fluoxetine and Pimozide have a documented major interaction in FDA labeling.

FDA drug labeling documents a major-severity interaction between Fluoxetine and Pimozide. 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

Fluoxetine

Selective Serotonin Reuptake Inhibitor (SSRI)

Drug B

Pimozide

Typical Antipsychotic

How They Interact

Taking these two drugs together can cause dangerous changes to the electrical rhythm of your heart. This is known as QT prolongation and can be very serious.

FDA Label Information

NSAIDs, Aspirin, Warfarin): May potentiate the risk of bleeding ( 7.4 ) Drugs Tightly Bound to Plasma Proteins: May cause a shift in plasma concentrations ( 7.6 , 7.7 ) Olanzapine: When used in combination with fluoxetine, also refer to the Drug Interactions section of the package insert for Symbyax ( 7.7 ) Drugs that Prolong the QT Interval: Do not use fluoxetine with thioridazine or pimozide. 7.7 Potential for Fluoxetine to affect Other Drugs Pimozide — Concomitant use in patients taking pimozide is contraindicated. Pimozide can prolong the QT interval.

Frequently Asked Questions

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

Compiled FDA labeling labels this pair major. 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 Pimozide's 24. In the major band specifically: Fluoxetine has 6 (also Aspirin, Warfarin, Olanzapine, Thioridazine); Pimozide has 12 (also Aprepitant, Citalopram, Clarithromycin, Darunavir).

What mechanism field is on file for Fluoxetine and Pimozide?

Taking these two drugs together can cause dangerous changes to the electrical rhythm of your heart. This is known as QT prolongation and can be very serious.

Pimozide carries more major-labeled pairs than Fluoxetine

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

Pimozide has 12 major-labeled pairs vs Fluoxetine's 6.

Fluoxetine

6 major · 19 moderate · 43 minor · 68 total

Pimozide

12 major · 0 moderate · 12 minor · 24 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.