Relationship between T4 and T3 in Hashimoto's

Posted by krisjb1 @krisjb1, Apr 13, 2021

When I look up this issue online I can't find much to explain why my T4 number 5.6, is normal according to LabCorp, and my T3 (free) ,4.8 is high. According to the lab it should be no higher than 4.4. My free T4 is .85 which is at the low end of the scale. Since my TSH is 5.00 I guess it is struggling to churn out hormones on my NP thyroid dosage of 60 mg but I have been told that increasing the NP thyroid dosage to decrease the TSH would be a mistake because it would increase my T3 (Free) making me hyperthyroid. So, could this be an adrenal problem? If so would increasing cortisol help?

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@krisjb1 Welcome to Mayo Clinic Connect, a place to give and get support.

So that you can more likely receive the support you seek I'm inviting members @kjo1 @brens5tzus @devinsmom @sparshall @kidsmomof9 @rarelybees2889 @fighter, who have discussed a similar topic in the past.

May I ask what information and guidance your provider has given regarding your question(s)?


My endocrinologist has not been as attentive to my results as I would like so I am choosing a new dr. and asking for thyroid imaging which has been only done once by my present endocrinolgist.


I have struggled to keep my T4 in normal range for years. I suggest with your Doctors input walking at least 2 miles a day and avoiding soy
which seemed to raise mine also the TSH seems to high so you might want to get a new Blood test I had 1 last year that was way off and my Nurse Daughter suggested getting a new lab test and the second one done before 10 am was almost normal.


I am considering if STTM( (Stop the Thyroid Madness) which suggests that "pooling" of T 3 due to malabsorption caused by an issue with cortisol is right. Perhaps testing for cortisol and supplementation with hydrocortisone if need be is the way to address the issue of high free t3 in the blood.

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