What the FDA labels say about taking them together
Fludrocortisone and rifampin
Fludrocortisone's FDA label of October 29, 2024 names rifampin in its drug interactions section; the rifampin label PlainMeds reads does not name fludrocortisone. The fludrocortisone label: “Barbiturates, phenytoin, or rifampin –increased metabolic clearance of fludrocortisone acetate because of the induction of hepatic enzymes.”
Check it at the source: the fludrocortisone FDA label on DailyMed (effective October 29, 2024, Zydus Lifesciences Limited); the rifampin FDA label on DailyMed (effective February 11, 2026, Lupin Pharmaceuticals, Inc.).
What does the fludrocortisone label say about rifampin?
Fludrocortisone label, drug interactionsBarbiturates, phenytoin, or rifampin –increased metabolic clearance of fludrocortisone acetate because of the induction of hepatic enzymes.
Source: FDA drug label (Fludrocortisone acetate), Zydus Lifesciences Limited, effective October 29, 2024 (SPL set 6c4a7d2d-00a4-4d80-ab4c-2afd4e4f614e), via openFDA; the full label on DailyMed
What does the rifampin label say about fludrocortisone?
Rifampin's label (effective February 11, 2026) does not name fludrocortisone in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (rifampin), Lupin Pharmaceuticals, Inc., effective February 11, 2026 (SPL set b56004f0-f23d-47f6-80c7-39884fccbccc), 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
| Fludrocortisone | Rifampin | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.311 per tablet 0.1 mg tablet | $0.679 per capsule 300 mg capsule |
| Shortage now | No current entry | In shortage |
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