What the FDA labels say about taking them together
Multiple vitamins and thiamine
Multiple vitamins's FDA label of November 20, 2024 names thiamine in its drug interactions section; the thiamine label PlainMeds reads does not name multiple vitamins. The multiple vitamins label: “Thiamine, riboflavin, pyridoxine, niacinamide, and ascorbic acid decrease activities of erythromycin, kanamycin, streptomycin, doxycycline, and lincomycin”
Check it at the source: the multiple vitamins FDA label on DailyMed (effective November 20, 2024); the thiamine FDA label on DailyMed (effective July 22, 2026, Sagent Pharmaceuticals).
What does the multiple vitamins label say about thiamine?
Multiple vitamins label, drug interactionsEffect of INFUVITE PEDIATRIC on other drugs: Thiamine, riboflavin, pyridoxine, niacinamide, and ascorbic acid decrease activities of erythromycin, kanamycin, streptomycin, doxycycline, and lincomycin
Multiple vitamins label, warnings and precautionsAllergic Reactions: To thiamine may occur
Source: FDA drug label (Infuvite Adult, NDA021163), Sandoz Inc, effective November 6, 2024 (SPL set 14c7bfc5-07e8-400f-b8ff-5e4794dd2805), via openFDA
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 thiamine label say about multiple vitamins?
Thiamine's label (effective July 22, 2026) does 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 (thiamine hydrochloride), Sagent Pharmaceuticals, effective July 22, 2026 (SPL set 5982cf83-01d6-4acb-8373-339079b8a76e), 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 | Thiamine | |
|---|---|---|
| Labeled for | n/a | n/a |
| Boxed warning | No | No |
| Pharmacy cost (NADAC) | n/a | $2.25 per mL 200 mg/2 mL vial |
| 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