What the FDA labels say about taking them together
Digoxin and mefenamic acid
Mefenamic acid's FDA label of April 20, 2026 names digoxin in its drug interactions section; the digoxin labels PlainMeds reads (3) do not name mefenamic acid. The mefenamic acid label: “The concomitant use of mefenamic acid with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin.”
Check it at the source: the digoxin FDA label on DailyMed (effective December 5, 2024, Advanz Pharma (US) Corp.); the mefenamic acid FDA label on DailyMed (effective April 20, 2026, Lupin Pharmaceuticals, Inc.).
What does the digoxin label say about mefenamic acid?
Digoxin's label (effective December 5, 2024) and its 2 other brand-application labels do not name mefenamic acid in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (LANOXIN), Advanz Pharma (US) Corp., effective December 5, 2024 (SPL set d91e3646-4c63-4512-ab22-db39c085c4dc), via openFDA; the full label on DailyMed
What does the mefenamic acid label say about digoxin?
Mefenamic acid label, drug interactionsClinical Impact: The concomitant use of mefenamic acid with digoxin has been reported to increase the serum concentration and prolong the half-life of digoxin. Intervention: During concomitant use of mefenamic acid and digoxin, monitor serum digoxin levels.
Source: FDA drug label (Mefenamic Acid), Lupin Pharmaceuticals, Inc., effective April 20, 2026 (SPL set d15733a9-d5fd-4d5f-86ce-e7ed8c706c7f), 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
| Digoxin | Mefenamic acid | |
|---|---|---|
| Labeled for | Heart failure, Atrial fibrillation | Pain |
| Boxed warning | No | Yes |
| Pharmacy cost (NADAC) | $0.133 per tablet 125 mcg tablet | $0.948 per capsule 250 mg capsule |
| Shortage now | No current entry | No current entry |
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