What the FDA labels say about taking them together
Diazepam and rifampin
Diazepam's FDA label (Valtoco) of June 3, 2026 names rifampin in its drug interactions section; the rifampin label PlainMeds reads does not name diazepam. The diazepam label: “Inducers of CYP2C19 and CYP3A4 Inducers of CYP2C19 (e.g., rifampin) and CYP3A4 could increase the rate of diazepam elimination; therefore, efficacy of VALTOCO may be decreased.”
Check it at the source: the diazepam FDA label on DailyMed (effective August 11, 2026, Waylis Therapuetics LLC); the rifampin FDA label on DailyMed (effective February 11, 2026, Lupin Pharmaceuticals, Inc.).
What does the diazepam label say about rifampin?
Valtoco label (Neurelis, Inc, June 3, 2026), drug interactionsInducers of CYP2C19 and CYP3A4 Inducers of CYP2C19 (e.g., rifampin) and CYP3A4 (e.g., carbamazepine, phenytoin, dexamethasone, and phenobarbital) could increase the rate of diazepam elimination; therefore, efficacy of VALTOCO may be decreased.
Source: FDA drug label (Valtoco, NDA211635), Neurelis, Inc, effective June 3, 2026 (SPL set 1a8bcc90-68fa-474d-832c-0df01e825f39), via openFDA
Source: FDA drug label (Valium), Waylis Therapuetics LLC, effective August 11, 2026 (SPL set 260e2041-2bb3-482f-850e-b5d47a7bdbe6), via openFDA; the full label on DailyMed
What does the rifampin label say about diazepam?
Rifampin's label (effective February 11, 2026) does not name diazepam 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
| Diazepam | Rifampin | |
|---|---|---|
| Labeled for | Anxiety, Muscle spasms and spasticity | n/a |
| Boxed warning | Yes | No |
| Pharmacy cost (NADAC) | $0.0283 per tablet 10 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