What the FDA labels say about taking them together
Rifabutin and rifampin
Rifabutin's FDA label of September 1, 2026 names rifampin in its drug interactions section; the rifampin label PlainMeds reads does not name rifabutin. The rifabutin label: “Theophylline 5 mg/kg 300 mg for 14 days Healthy subjects ND ↔ Other drugs The structurally similar drug, rifampin, is known to reduce the plasma concentrations of a number of other drugs.”
Check it at the source: the rifabutin FDA label on DailyMed (effective September 1, 2026, REMEDYREPACK INC.); the rifampin FDA label on DailyMed (effective February 11, 2026, Lupin Pharmaceuticals, Inc.).
What does the rifabutin label say about rifampin?
Rifabutin label, drug interactionsTheophylline 5 mg/kg 300 mg for 14 days Healthy subjects (11) ND ↔ Other drugs The structurally similar drug, rifampin, is known to reduce the plasma concentrations of a number of other drugs (see prescribing information for rifampin).
Rifabutin label, warningsAdministration of rifabutin as a single agent to patients with active tuberculosis is likely to lead to the development of tuberculosis that is resistant both to rifabutin and to rifampin.
Source: FDA drug label (Rifabutin), NDA050689 (Pfizer), as published by REMEDYREPACK INC., effective September 1, 2026 (SPL set 25a60937-cbbe-4a50-994f-2ce15203f589), via openFDA; the full label on DailyMed
What does the rifampin label say about rifabutin?
Rifampin's label (effective February 11, 2026) does not name rifabutin 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
| Rifabutin | Rifampin | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $8.14 per capsule 150 mg capsule | $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