Brexpiprazole and Fluoxetine Interaction

Drug interaction information between Brexpiprazole and Fluoxetine.

Brexpiprazole and Fluoxetine have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Brexpiprazole 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

Brexpiprazole

Atypical Antipsychotic

Drug B

Fluoxetine

Selective Serotonin Reuptake Inhibitor (SSRI)

How They Interact

Fluoxetine blocks an enzyme that breaks down brexpiprazole, but the effect is not strong enough to require a change in dose for patients with depression.

FDA Label Information

7 DRUG INTERACTIONS Factors Dosage Adjustments for REXULTI ( 2.7 ) Strong CYP2D6 REXULTI may be administered without dosage adjustment in patients with MDD when administered with strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine). Strong CYP2D6 Inhibitors In the clinical studies examining the adjunctive use of REXULTI in the treatment of MDD, dosage was not adjusted for strong CYP2D6 inhibitors (e.g., paroxetine, fluoxetine).

Frequently Asked Questions

What SPL severity band is on file for Brexpiprazole + 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 Brexpiprazole's 9. In the minor band specifically: Brexpiprazole has 9 (also Omeprazole, Rosuvastatin, Bupropion, Paroxetine); Fluoxetine has 43 (also Ketoconazole, Lithium, Moxifloxacin, Erythromycin).

What mechanism field is on file for Brexpiprazole and Fluoxetine?

Fluoxetine blocks an enzyme that breaks down brexpiprazole, but the effect is not strong enough to require a change in dose for patients with depression.

Fluoxetine carries more major-labeled pairs than Brexpiprazole

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

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

Brexpiprazole

0 major · 0 moderate · 9 minor · 9 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.