Leflunomide and Duloxetine Interaction

Drug interaction information between Leflunomide and Duloxetine.

Leflunomide and Duloxetine have a documented minor interaction in FDA labeling.

FDA drug labeling documents a minor-severity interaction between Leflunomide and Duloxetine. 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

Leflunomide

Disease-Modifying Antirheumatic Drug (DMARD)

Drug B

Duloxetine

Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)

How They Interact

Leflunomide speeds up how fast your body breaks down duloxetine, which can lower the amount of medicine in your system and make it less effective.

FDA Label Information

In patients taking leflunomide, exposure of drugs metabolized by CYP1A2 (e.g., alosetron, duloxetine, theophylline, tizanidine) may be reduced.

Frequently Asked Questions

What SPL severity band is on file for Leflunomide + Duloxetine?

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?

Leflunomide has 20 labeled pairs on file vs Duloxetine's 18. In the minor band specifically: Leflunomide has 20 (also Atorvastatin, Rosuvastatin, Simvastatin, Furosemide); Duloxetine has 17 (also Fluoxetine, Famotidine, Buspirone, Paroxetine).

What mechanism field is on file for Leflunomide and Duloxetine?

Leflunomide speeds up how fast your body breaks down duloxetine, which can lower the amount of medicine in your system and make it less effective.

Leflunomide's labeled portfolio outnumbers Duloxetine

SPL source-record counts only. This page's band is minor · classes on file: Leflunomide (Disease-Modifying Antirheumatic Drug (DMARD)); Duloxetine (Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)).

Leflunomide

0 major · 0 moderate · 20 minor · 20 total

Duloxetine

0 major · 1 moderate · 17 minor · 18 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.