What the FDA labels say about taking them together
Multiple vitamins and phenytoin
Multiple vitamins's FDA label of November 20, 2024 names phenytoin in its drug interactions section; the phenytoin labels PlainMeds reads (2) do not name multiple vitamins. The multiple vitamins label: “Folic acid may decrease phenytoin blood levels and increase risk of seizure activity”
Check it at the source: the multiple vitamins FDA label on DailyMed (effective November 20, 2024); the phenytoin FDA label on DailyMed (effective October 15, 2024, Mylan Pharmaceuticals Inc.).
What does the multiple vitamins label say about phenytoin?
Multiple vitamins label, drug interactionsFolic acid may decrease phenytoin blood levels and increase risk of seizure activity
Source: FDA drug label (Infuvite Pediatric), Sandoz Inc, effective November 20, 2024 (SPL set 6d06546e-8b0a-4490-82d9-397bd902a044), via openFDA; the full label on DailyMed
What does the phenytoin label say about multiple vitamins?
Phenytoin's label (effective October 15, 2024) and its 1 other brand-application label do not name multiple vitamins in these sections. A label lists what its studies and reports found; it is not a complete list.
Source: FDA drug label (Phenytek), Mylan Pharmaceuticals Inc., effective October 15, 2024 (SPL set 0f94c791-8b07-4b41-927e-c9f28bec5f60), 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
| Multiple vitamins | Phenytoin | |
|---|---|---|
| Labeled for | n/a | Seizures and epilepsy |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $0.145 per capsule 100 mg capsule |
| Shortage now | No current entry | 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