Can I Take These?

Can You Take Levothyroxine and Vitamin B12 Together?

No documented interaction was identified between vitamin B12 and levothyroxine in the sources reviewed.

No documented interaction identifiedEvidence: Moderate

See the full Levothyroxine page and Vitamin B12 page for other reviewed interactions and reference information.

What the interaction means

Levothyroxine's FDA label's only "vitamin B12" hit is inside its generic pharmacologic-class taxonomy dropdown list, not a prose interaction statement. The NIH ODS vitamin B12 fact sheet's interactions section names only gastric acid inhibitors and metformin -- levothyroxine is not named.

No documented interaction between Levothyroxine and Vitamin B12 was identified in the authoritative sources reviewed. This is not a guarantee that no interaction exists for every dose, formulation, or individual -- it means the sources checked did not document one.

Practical context

Both substances' own current authoritative sources were checked directly; the taxonomy-list mention was deliberately not treated as a real interaction claim.

What the sources say

Vitamin B12 — Consumer — NIH Office of Dietary SupplementsLevothyroxine Sodium Capsules — FDA Prescribing Information — YARAL Pharma, Inc. (via DailyMed, U.S. National Library of Medicine)

Last reviewed 2026-08-23

Medical information disclaimer: this information is general and educational. It does not diagnose conditions, prescribe treatment, or determine whether a combination is safe for you personally. Follow your prescription label and ask a pharmacist or clinician before starting, stopping, or combining products. Full disclaimer.

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