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Can Taking Synthroid Half An Hour Before A Blood Test For Vitamin-B12 Cause It To Affect Results?
Posted on
Mon, 25 Jun 2018
Medically reviewed by
Ask A Doctor - 24x7 Medical Review Team
Mon, 25 Jun 2018
Answered on
Thu, 6 Jan 2022
Last reviewed on
Question : An taking synthroid 1/2 hour before a blood test for vitamin b 12 cause it show as being high
Brief Answer:
in most persons, no serious cause, not linked to synthroid
Detailed Answer:
Hi,
The use of thyroid hormone replacement, such as synthroid, does not have any effect on the result of vitamin b12 levels on a test.
High B12 can be due to - (1) increased intake of vitamin b12 eg excess multivitamins
(2)excess release of vitamin b12 for storage in the body, it then enters the blood stream where it is detected by blood tests
(3) there is a protein in the body that b12 attaches to and it transports or carries the vitamin b12. If this protein does not hold or bind the vitamin 12 properly then more would be in the blood stream
In the majority of persons, the excess vitamin b12 is not significant.
Rarely it can be associated with blood disorders .
Even less commonly, it can be associated with some cancers such as liver. As mentioned, in most persons, there is no serious cause found.
You may need additional bloods, if not already done
I hope this helps , feel free to ask any other questions
in most persons, no serious cause, not linked to synthroid
Detailed Answer:
Hi,
The use of thyroid hormone replacement, such as synthroid, does not have any effect on the result of vitamin b12 levels on a test.
High B12 can be due to - (1) increased intake of vitamin b12 eg excess multivitamins
(2)excess release of vitamin b12 for storage in the body, it then enters the blood stream where it is detected by blood tests
(3) there is a protein in the body that b12 attaches to and it transports or carries the vitamin b12. If this protein does not hold or bind the vitamin 12 properly then more would be in the blood stream
In the majority of persons, the excess vitamin b12 is not significant.
Rarely it can be associated with blood disorders .
Even less commonly, it can be associated with some cancers such as liver. As mentioned, in most persons, there is no serious cause found.
You may need additional bloods, if not already done
I hope this helps , feel free to ask any other questions
Above answer was peer-reviewed by :
Dr. Chakravarthy Mazumdar
Answered by
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