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Methuen, MA
A 29-year-old female asked:

Thyroid ultrasound = no concern ; thy. antibody test showed no autoimmune cause. tsh still high, even on synthroid. ft4 high end of normal. causes???

1 doctor answer4 doctors weighed in
Dr. Richard Zimon
Internal Medicine 60 years experience
Two thoughts: 1. This sounds like primary thyroid failure ("simple" HYPO-thyroidism) which is "borderline" but is causing the high TSH (Think of the TSH "trying" to "waken" the "sleeping" gland. 2. Synthroid per se (=thyroxine (T-4) is a POOR TSH suppressant ...it needs to be converted to T-3 to suppress the TSH..thus a SWITCH in your thyroid pills to a T-3 may help! Hope this is helpful Dr Z

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Last updated Oct 12, 2020


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