What the FDA labels say about taking them together
Rifampin and sorafenib
Sorafenib's FDA label of August 28, 2023 names rifampin in its drug interactions section; the rifampin label PlainMeds reads does not name sorafenib. The sorafenib label: “Drugs on NEXAVAR Strong CYP3A4 Inducers The concomitant use of NEXAVAR with rifampin, a strong CYP3A4 inducer decreased the mean AUC of sorafenib, which may decrease the antitumor activity.”
Check it at the source: the rifampin FDA label on DailyMed (effective February 11, 2026, Lupin Pharmaceuticals, Inc.); the sorafenib FDA label on DailyMed (effective August 28, 2023, Bayer HealthCare Pharmaceuticals Inc.).
What does the rifampin label say about sorafenib?
Rifampin's label (effective February 11, 2026) does not name sorafenib 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
What does the sorafenib label say about rifampin?
Sorafenib label, drug interactionsDrugs on NEXAVAR Strong CYP3A4 Inducers The concomitant use of NEXAVAR with rifampin, a strong CYP3A4 inducer decreased the mean AUC of sorafenib, which may decrease the antitumor activity [see Clinical Pharmacology ( 12.3 )].
Source: FDA drug label (Nexavar), Bayer HealthCare Pharmaceuticals Inc., effective August 28, 2023 (SPL set b50667e4-5ebc-4968-a646-d605058dbef0), 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
| Rifampin | Sorafenib | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.679 per capsule 300 mg capsule | n/a |
| Shortage now | In shortage | 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