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San Antonio, TX
A 48-year-old male asked:

Are there any interactions or concerns regarding taking the amino acid l-tyrosine and the thyroid med synthroid? drug interdiction sites dont have much on the two together as one is a drug and the other i guess isnt. mixed chatter on the subject.

2 doctor answers2 doctors weighed in
Dr. Stuart Hickerson
Family Medicine 34 years experience
L-tyrosine: This amino acid is one of the basic amino acids your thyroid uses to make thyroid hormone. If you are taking synthroid this can lead to excess thyroid in the serum and signs of hyperthyroidism. Some times a provider will do this to improve response to thyroid replacement, but should probably not be done unless your provider thinks this is appropriate.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. John Berryman
Obstetrics and Gynecology 56 years experience
Tyrosine/Synthroid ?: Tyrosine and Synthroid do not interact in an adverse way. Check with your physician who prescribed the Synthroid, as he/she may know other medical history which would influence taking both.
Created for people with ongoing healthcare needs but benefits everyone.
Last updated Feb 25, 2020
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