Low T3 and T4, normal TSH

[wpconway25]

Hey everyone. New to the forum and could really use some help understanding what could bc going on with my thyroid. I have tested FT4 barely in range, FT3 way below range, and elevated reverse T3. I would expect my TSH to be elevated given these values but it is quite normal.

I was wondering if anyone has seen this before and has some insight on where to start looking. Are there other hormone deficiencies that could cause this? Gut issues like parasites? Not really sure where to start.

 

[TAG145]

Just a quick question: What is your TSH that you are considering it "normal"?

 

[wpconway25]

1.5 which I know is on the upper end, but with a FT3 at 1.9pg/ml, I would assume it would be higher.

 

[wpconway25]

Just a quick question: What is your TSH that you are considering it "normal"?

1.5 which I know is on the upper end, but with a FT3 at 1.9pg/ml, I would assume it would be higher.*

 

[youngsinatra]

High cortisol can lower TSH, which suppresses thyroid hormone synthesis and increases RT3.

 

[wpconway25]

High cortisol can lower TSH, which suppresses thyroid hormone synthesis and increases RT3.

I do have mildly elevated cortisol on a morning blood test. How do I know what is causing what? I have also read that elevated cortisol could be a result of low thyroid function?

 

[youngsinatra]

I do have mildly elevated cortisol on a morning blood test. How do I know what is causing what? I have also read that elevated cortisol could be a result of low thyroid function?

Yes. It can go both ways. It’s hard to tell.

Low Reverse T3 A Reliable, Sensitive and Specific in Diagnosis of Central Hypothyroidism

In primary hypothyroidism, cortisol clearance is very impaired, but in primary hypothyroidism reverse T3 is usually low.

A high reverse T3 already tells that you produce sufficient amount of T4, because you cannot produce it without it.

 

[wpconway25]

Yes. It can go both ways. It’s hard to tell.

Low Reverse T3 A Reliable, Sensitive and Specific in Diagnosis of Central Hypothyroidism

In primary hypothyroidism, cortisol clearance is very impaired, but in primary hypothyroidism reverse T3 is usually low.

A high reverse T3 already tells that you produce sufficient amount of T4, because you cannot produce it without it.

Thank you for your response. Do you have any insight into what potential causes could be if not central hypo, if given elevated cortisol is a result of the thyroid and not the inverse? I have spent months dialing in sleep, diet, and anything else that could help bring down cortisol with no luck.

 

[youngsinatra]

Thank you for your response. Do you have any insight into what potential causes could be if not central hypo, if given elevated cortisol is a result of the thyroid and not the inverse? I have spent months dialing in sleep, diet, and anything else that could help bring down cortisol with no luck.

I don’t know. How high is your cortisol? (Above the reference range?)

Have your adrenals been investigated by a doc? (adrenal tumor or something could be a more rare cause of elevated cortisol, but I think you said mildly elevated right?)

 

[wpconway25]

I don’t know. How high is your cortisol? (Above the reference range?)

Have your adrenals been investigated by a doc? (adrenal tumor or something could be a more rare cause of elevated cortisol, but I think you said mildly elevated right?)

Yeah morning cortisol has been tested between 17 and 20 ug/dl with high end of range being 16.

 

[youngsinatra]

Yeah morning cortisol has been tested between 17 and 20 ug/dl with high end of range being 16.

Hmm.. What does you doc say about it?

 

[TAG145]

Another good site for detailed thyroid issues and even optimal lab ranges is Stop the Thyroid Madness™ - Hypothyroidism and thyroid mistreatment

I have been battling sub optimal thyroid levels for 20 years mostly because there are not many doctors who are knowledgeable. Right now I'm on compounded T3 & T4, trying to rule out additives. It can be really complicated...I hope you are able to figure it out.

 

[ecstatichamster]

cortisol isn't necessarily high but if it doesn't cycle properly that is a problem and one that doesn't often show up on the tests where you get maybe two levels tested for an entire 24 hour period.