1 doctor weighed in:

Does B12 adversely affect synthroid (thyroxine)?

1 doctor weighed in
Dr. Donald Colantino
Internal Medicine

In brief: No

Taking vit B12 would not affect or interact with synthroid (thyroxine).
High doses of B12 are harmless as your body simply excretes the excess amount.

In brief: No

Taking vit B12 would not affect or interact with synthroid (thyroxine).
High doses of B12 are harmless as your body simply excretes the excess amount.
Dr. Donald Colantino
Dr. Donald Colantino
Thank
Get help from a real doctor now
Dr. Jack Hinkle
Board Certified,
389K people helped
Continue
111,000 doctors available
Read more answers from doctors