Help with T3 / T4

[aHarness]

So to be clear, I shouldn't be worried if the Free T3 on thyroid medication is lower than the Free T3 without thyroid medication? My blood draw was 10 hours after taking my T4

Are you taking t3 too? Sorry, I assumed you were. But either way @Black Beard have a great explanation.

 

[juicin]

T3 didnt go up cause the half life is very short, don't worry about that. With T3, you don't really look at the numbers because they fluctuate too much.


You're on 150 mcg T4 and how much T3? Did you take T4 and T3 before the labs or you skipped? Is the T3 UGL or from a pharmacy?

No, I’m not on any T3. Just 150 mcg T4 like you suggested.

It is UGL. Doc wouldn’t prescribe anything.

This just happens to be the first time “free T3” was tested. Before this it was always total t3 tested. Unfortunately.

Yes I did take T4 the morning of the test. I’d say blood drawn 6-7 hours after I took it.

 

[nothuman]

Yeah, that happens normally.

You mean with T4 solo or with T3? Cause the physiological reasons will be different


T4 solo: Taking T4 only creates a higher than normal T4 to T3 ratio. Your body will 1. stop secreting T3 directly and 2. downregulate conversion/deiodination of T4 to T3 due to lower TSH.


T4+T3 and T3 solo: Body downregulates T4 and T3 secretion and the short half life of T3 makes it appear to be lower than baseline (if you test 12-24 hours after last dose)


The T4 monotherapy T4 to T3 ratio IS unphysiological which creates a lot of debate among endo researchers whether that's good or bad.


If you feel good i wouldnt worry about it too much, however, many patients have subtle deficits if they don't take T3. (Skin/hair quality, energy, cognitive function and even libido).


If you use GH, that will increase T4 to T3 conversion. Have you ever tried using only 5 mcg T3 with your T4?

It can make you flat at first sometimes but the body adjusts after a few weeks.

Thank you so much! As clear of an answer as I could have asked for. I feel like I know a lot about the topic in general but this particular possibility of lowering of Free T3 on blood tests is not something I often see talked about.

Are you taking t3 too? Sorry, I assumed you were. But either way @Black Beard have a great explanation.

I’ve actually tried both T4/T3 and T4 alone and in both cases, I’ve had lower Free T3’s than baseline on a blood test.

 

[Black Beard]

No, I’m not on any T3. Just 150 mcg T4 like you suggested.

It is UGL. Doc wouldn’t prescribe anything.

This just happens to be the first time “free T3” was tested. Before this it was always total t3 tested. Unfortunately.

Yes I did take T4 the morning of the test. I’d say blood drawn 6-7 hours after I took it.

How are you feeling ? If you can't get doc Rx, i recommend getting pharma grade thyroid meds from overseas pharmacies like reliable Rx or all day chemist.


Thyroid meds are extremely easy to misdose when you make tablets/capsules because it's in micrograms instead of mg. 100 mcg levo is only 0.1 mg, imagine how easily you can mess that up in a UGL.


Your Free T4 looks good, especially if that's after skipping T4 before the blood draw. You can either way a few months if you still have a few symptoms to see if they get better or add a small amount of T3 (5-10 mcg)

 

[juicin]

How are you feeling ? If you can't get doc Rx, i recommend getting pharma grade thyroid meds from overseas pharmacies like reliable Rx or all day chemist.


Thyroid meds are extremely easy to misdose when you make tablets/capsules because it's in micrograms instead of mg. 100 mcg levo is only 0.1 mg, imagine how easily you can mess that up in a UGL.


Your Free T4 looks good, especially if that's after skipping T4 before the blood draw. You can either way a few months if you still have a few symptoms to see if they get better or add a small amount of T3 (5-10 mcg)

No, I did take T4 the day of my blood draw. That’s the one thing you told me not to do that I forgot about.

But Black Beard, why is my free T3 in range, but my total T3 is even lower than my last labs I posted from August and october?

Does this mean maybe I never even had a problem to begin with?

I wish I had tested my free t3 on my last labs, but this just happened to be the first time I tested them.

And to answer your question, I feel pretty good.

 

[Black Beard]

No, I did take T4 the day of my blood draw. That’s the one thing you told me not to do that I forgot about.

But Black Beard, why is my free T3 in range, but my total T3 is even lower than my last labs I posted from August and october?

Does this mean maybe I never even had a problem to begin with?

I wish I had tested my free t3 on my last labs, but this just happened to be the first time I tested them.

And to answer your question, I feel pretty good.

Yeah, so you could bump the T4 a bit if you feel like it, because that free T4 is slightly higher right after the pill. Something like 15-25% higher.



Glad you are feeling better, you can stay there for a bit or trial small dose T3. Lots of options, but you are close to optimized with that test result and how you are feeling. Congratulations



When you take T4, your body 1. Produces less T3 from direct thyroid secretion 2. Reduces conversion of T4 to T3. Many patients on T4 only have higher T4 to T3 ratio than is natural, which is why many benefit from adding a low dose of T3.

 

[juicin]

Yeah, so you could bump the T4 a bit if you feel like it, because that free T4 is slightly higher right after the pill. Something like 15-25% higher.



Glad you are feeling better, you can stay there for a bit or trial small dose T3. Lots of options, but you are close to optimized with that test result and how you are feeling. Congratulations



When you take T4, your body 1. Produces less T3 from direct thyroid secretion 2. Reduces conversion of T4 to T3. Many patients on T4 only have higher T4 to T3 ratio than is natural, which is why many benefit from adding a low dose of T3.

But how does this affect total t3 and free t3? I would think if my total t3 is in range, so should my free t3. But it’s not… total t3 is just as low on my last labs. I wish I had tested free t3 back then.

 

[Black Beard]

But how does this affect total t3 and free t3? I would think if my total t3 is in range, so should my free t3. But it’s not… total t3 is just as low on my last labs. I wish I had tested free t3 back then.

"In range" means shit.


That lab range you see there, half of that are levels you see in hypothyroid people. Once you see "low" that's generally severe hypothyroidism.

Example: Free T4 under 1 ng/dL is normal until you get you 0.7, but between 0.7-1.1 ng/dL you are looking at a very sluggish and compromised thyroid.

I have seen patients with TSH +50 with 0.7 Free T4 and i've seen them with 0.7 Free T4 with TSH of 1. Clinicians will ignore the latter and only treat the former because they only look at tsh but thats another topic.