What the FDA labels say about taking them together
Phenobarbital and propranolol
Propranolol's FDA label of January 15, 2026 names phenobarbital in its drug interactions section; the phenobarbital labels PlainMeds reads (2) do not name propranolol. The propranolol label: “CYP1A2 inducers (phenytoin, phenobarbital) or CYP2C19 inducers (rifampin) decrease propranolol plasma concentration when co-administered.”
Check it at the source: the phenobarbital FDA label on DailyMed (effective August 27, 2026); the propranolol FDA label on DailyMed (effective January 15, 2026, Mylan Pharmaceuticals Inc.).
What does the phenobarbital label say about propranolol?
Phenobarbital's label (effective August 27, 2026) and its 1 other brand-application label do not name propranolol in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Phenobarbital), Chartwell RX, LLC, effective August 27, 2026 (SPL set 74428144-fb24-40a5-a670-3b876e2d116c), via openFDA; the full label on DailyMed
What does the propranolol label say about phenobarbital?
Propranolol label, drug interactionsInducers of Hepatic Drug Metabolism Blood levels of propranolol may be decreased by co-administration with inducers such as rifampin, ethanol, phenytoin, and phenobarbital.
Hemangeol label (Pierre Fabre Pharmaceuticals, Inc., June 25, 2026), drug interactionsCYP1A2 inducers (phenytoin, phenobarbital) or CYP2C19 inducers (rifampin) decrease propranolol plasma concentration when co-administered.
Source: FDA drug label (Hemangeol, NDA205410), Pierre Fabre Pharmaceuticals, Inc., effective June 25, 2026 (SPL set b6f9dd2a-632b-87eb-70f0-b2064d7ed48a), via openFDA
Source: FDA drug label (Propranolol Hydrochloride), Mylan Pharmaceuticals Inc., effective January 15, 2026 (SPL set b94dcec7-7633-4a33-9cea-48161adeaf93), 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
| Phenobarbital | Propranolol | |
|---|---|---|
| Labeled for | Seizures and epilepsy | High blood pressure, Angina, Atrial fibrillation, Migraine |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | $0.213 per tablet 100 mg tablet | $0.0493 per tablet 20 mg tablet |
| Shortage now | A presentation being discontinued | 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