Risperidone and Fluoxetine Interaction

Drug interaction information between Risperidone and Fluoxetine.

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

FDA drug labeling documents a minor-severity interaction between Risperidone 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

Risperidone

Atypical Antipsychotic

Drug B

Fluoxetine

Selective Serotonin Reuptake Inhibitor (SSRI)

How They Interact

Fluoxetine stops the body from breaking down risperidone properly, which can cause the drug to build up to higher levels in your blood.

FDA Label Information

( 7.1 ) Fluoxetine, paroxetine, and other CYP 2D6 enzyme inhibitors increase plasma concentrations of risperidone. ( 7.1 ) 7.1 Pharmacokinetic-related Interactions The dose of risperidone tablets should be adjusted when used in combination with CYP2D6 enzyme inhibitors (e.g., fluoxetine, and paroxetine) and enzyme inducers (e.g., carbamazepine) [see Table 18 and Dosage and Administration (2.5) ]. Summary of Effect of Coadministered Drugs on Exposure to Active Moiety (Risperidone + 9-Hydroxy-Risperidone) in Healthy Subjects or Patients with Schizophrenia Coadministered Drug Dosing Schedule...

Frequently Asked Questions

What SPL severity band is on file for Risperidone + 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 Risperidone's 20. In the minor band specifically: Risperidone has 9 (also Clozapine, Dopamine, Bupropion, Carbidopa/Levodopa); Fluoxetine has 43 (also Ketoconazole, Lithium, Moxifloxacin, Erythromycin).

What mechanism field is on file for Risperidone and Fluoxetine?

Fluoxetine stops the body from breaking down risperidone properly, which can cause the drug to build up to higher levels in your blood.

Fluoxetine's labeled portfolio outnumbers Risperidone

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

Risperidone

6 major · 5 moderate · 9 minor · 20 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.