I have my appointment with the endo this afternoon.
I have read that if you’re on T3 and T4, your TSH should be within the normal range.
my T3 was 5.7 (with 6.8 being the top of the range) and my T4 was 21.3 (with 22 being the top of the range). My TSH is suppressed.
Please can someone tell me if it’s okay for the TSH to be suppressed when on both. Is there research that I could look at? I have looked but nothing comes up.
Thank you very much!
T3 naturally lowers both TSH and FT4
The drop will depend on how much T3 you are taking....I guess it isn't much because your FT4 is close to the top of the range.
Please can someone tell me if it’s okay for the TSH to be suppressed when on both
Yes!
The TSH isn't really important, it's a pituitary, not a thyroid, hormone.....so ignore what you read re TSH. Following diagnosis and after medication it is not reliable marker for medicating.....for one thing it fluctuates throughout the day
thyroidpatients.ca/2021/07/...
and
bmcendocrdisord.biomedcentr...
Time for a reassessment of the treatment of hypothyroidism
John E. M. Midgley, Anthony D. Toft, Rolf Larisch, Johannes W. Dietrich & Rudolf Hoermann
How much T4 and T3 are you taking? Your levels seem to be on the high side.
High FT4 is not advisable it can cause other problems including possible susceptibility to cancer
How do you feel? Symptoms?
Good luck for the appointment...hopefully your endo is clued up.
PS....I'm now wondering if your serum T3 is actually reaching the nuclei of the cells in an adequate level..... where it attaches to T3 receptors and becomes active.
We expect cellular T3 level will match serum FT3 level but in rare cases this doesn't happen
It's relatively rare, but some of us need a higher serum FT3 level to achieve an adequate cellular T3 level....if a form of hormone resistance exists.
I have a form of Thyroid Hormone Resistance which requires a supraphysiological dose of T3....tho not suggesting you do.
Low cellular T3 = poor health
In your shoes I'd be considering reducing the T4 then increasing your T3....one hormone at a time.
It may involve some trial and error...and some time...to achieve your therapeutic dose.
Don't let this endo ramble on about TSH...tatty has given you good links re TSH
FT3 is the most important number followed by FT4
Hope this makes sense...I'm in a hurry right now so reply a tad rushed
Thank you very much for your detailed reply.
How much T4 and T3 are you taking? Your levels seem to be on the high side.
I’m taking 10mcg T3 and 100mcg T4.
How do you feel? Symptoms?
I’m having loads of symptoms. I had the SST last week. I have lost a lot of weight - 4kg. I was 55 and now I’m 50.8kg. My brain fog is horrible, dizziness, nausea, cramping, nails breaking, hair loss, feeling cold a lot (unless I’m having a hot flush!), exhausted all the time etc. That’s why I had the SST. I will get the results later.
I will talk to the endo about what you mention and see what he says. I do not think he’s clued up, nor do I think he’s of the opinion that TSH level doesn’t matter. It’s been suppressed the entire time I have had UAT (20 years). I went on T3 about 15 months ago.
Dr Toft wrote that to be on both you need your TSB in range. If only T4, it could be suppressed.
Thank you very much again for your reply.
It all sounds very familiar...so sorry you feel like this I totally emphasise
Dose - 10mcg T3 + 100mcg T4
FT4 at 21.3 with 22 being the top of the range
FT3 at 5.7 (with 6.8 being the top of the range
Looking at your symptoms they suggest ( mainly) undermedication... but losing weight is usually overmedication
I would suggest you lower the T4 ( the T3 may be causing a false low!).....your T4 to T3 conversion is possibly impaired but we cannot establish thar after T3 is added.
Instead I....p.ease keep us posted. had the Dio2 genetic test which showed I had inherited the polymorphism from both parents...so very poor conversion.
Might be worth considering....it is evidence to give to medics!
You have room to increase your T3/ FT3...over range FT3 usually suggests overmedication but you are not there yet!
However some of us need FT3 to be slightly over range if there is a degree of hormone resistance.
My TSH and FT4 are totally suppressed and my FT3 is in the clouds!
We are all different and that's what my body needs to function ( all in my bio)
I had to work this out myself with the help of a small group of experienced members and a great deal of reading.
The endo I saw was clueless and my GP though I was about to kill myself....I'm still here at age 78!!
Hope this endo helps
I agree that the majority of symptoms suggest under medication, with the exception of losing weight!
One of the biggest problems is the endo!!! I’d happily experiment to see what works and what doesn’t. If only he’d give me carte blanche to do that. I’d keep him abreast of what I’m doing. But that’s never going to happen. My GP would be much more open to that idea!
I will do as you suggest, and lower my T4. It will then in all likelihood go quite low. (Recently it was 18.2 but no T3 was tested.) There might then be a case for increasing the T3.
Did you have the genetic test done privately?
It’s amazing your T4 and TSH are suppressed but your T3 is very high. Do you have an endo who oversees your thyroid stuff now? What a pity you had one who was clueless. Sadly most are! How I wish Dr Toft hadn’t retired. I miss his knowledge and understanding hugely. I have been looking for someone like him ever since, but they don’t seem to exist.
The endo I saw was clueless and my GP though I was about to kill myself....I'm still here at age 78!!
As if you wouldn’t research first before doing that! This comment made me laugh!
No endo....I self medicate. My GP now accepts this and leaves me incontrol of my thyroid treatment
It’s amazing your T4 and TSH are suppressed but your T3 is very high.
Not amazing...to be expected....just how the body works
Yes, private thyroid genetic test
I will do as you suggest, and lower my T4. It will then in all likelihood go quite low. (Recently it was 18.2 but no T3 was tested.) There might then be a case for increasing the T3.
I did suggest you would need to increase T3 after reducing T4!
You really need to get your medication sorted out
Alter doses low and slow.
What I meant was that I could present it to the endo as a case to increase T3.
I really do need to get it sorted out. I’d like to feel well again.
Thank you for your replies. I’ll update once I have been to my appointment.
Just to add - the reason I started the T3 is because my T4 was out of range (high) and my T3 was low in the range. I managed to source the T3 and did it on the quiet for about six months before telling the GP. Knowledgeable people here told me I had a conversion problem. This group is so invaluable.
the reason I started the T3 is because my T4 was out of range (high) and my T3 was low in the range.
that is evidence!
But...
have you optimised vit D, vit B12, folate and ferritin....essential to support thyroid function/ conversion
I think so but will ask for them to be done. Ferritin I know is okay at 103.
I have had my appointment and I suggested I go down to 75mcg. I’ll be retested in six weeks.
Thank you for your advice. And I’ll ask for the other tests to be done.
both these posts have links to relevant research and other useful discussions re Low TSH / Risk vs Quality of life :
healthunlocked.com/thyroidu.... /tsh-is-just-the-opinion-of-your-pituitary-about-your-dose-but-your-pituitarys-opinion-is-a-bit-warped-once-you-take-thyroid-hormone.
healthunlocked.com/thyroidu... useful-evidence-that-tsh-between-0.04-0.4-has-no-increased-risk-to-patients-on-levothyroxine-updated-new-study-does-show-small-risk
Thank you very much! I will have a read of these before I go.
Low TSH with normal T3, T4. 
Suppressed TSH, on T3 trial
Is TSH suppression adversely affected by T3?
Blood tests TSH T4 T3 
TSH, FreeT4 & Free T3
