What the FDA labels say about taking them together
Duloxetine and leflunomide
Leflunomide's FDA label of June 4, 2025 names duloxetine in its drug interactions section; the duloxetine labels PlainMeds reads (2) do not name leflunomide. The leflunomide label: “In patients taking ARAVA, exposure of drugs metabolized by CYP1A2 may be reduced.”
Check it at the source: the duloxetine FDA label on DailyMed (effective May 14, 2024, SUN PHARMACEUTICAL INDUSTRIES, INC.); the leflunomide FDA label on DailyMed (effective June 4, 2025, sanofi-aventis U.S. LLC).
What does the duloxetine label say about leflunomide?
Duloxetine's label (effective May 14, 2024) and its 1 other brand-application label do not name leflunomide in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (DRIZALMA SPRINKLE), SUN PHARMACEUTICAL INDUSTRIES, INC., effective May 14, 2024 (SPL set b41423b8-dfec-4d79-ba3c-e43a87803d85), via openFDA; the full label on DailyMed
What does the leflunomide label say about duloxetine?
Leflunomide label, drug interactionsIn patients taking ARAVA, exposure of drugs metabolized by CYP1A2 (e.g., alosetron, duloxetine, theophylline, tizanidine) may be reduced.
Source: FDA drug label (Arava), sanofi-aventis U.S. LLC, effective June 4, 2025 (SPL set 320f63f2-fac3-4aee-aff8-85724e00ef52), via openFDA; the full label on DailyMed
These are the labels' own sentences. PlainMeds does not grade interactions; a pharmacist or prescriber can say what they mean for one person's medicines.
Both medicines on the record
| Duloxetine | Leflunomide | |
|---|---|---|
| Labeled for | Depression, Anxiety, Nerve pain and fibromyalgia, Pain | Rheumatoid arthritis |
| Boxed warning | Yes | Yes |
| Pharmacy cost (NADAC) | $0.102 per capsule 30 mg capsule | $0.324 per tablet 10 mg tablet |
| Shortage now | No current entry | A presentation being discontinued |
Source: FDA NDC Directory, CMS NADAC of October 7, 2026 and the FDA Drug Shortage Database (FDA files October 8, 2026)
What next?
- Check more medicines together
- up to five at once