Thyroid UK
87,471 members102,185 posts

Have I been set up to fail?

After 3 years of battling I have finally been put on a 3 months trial of T3. However, my endo has reduced my Levo to 100mg from 150mg before allowing me half a tiny tablet of T3. My TSH was 1, free T3 bottom of range and T4 mid range . I pushed for T3 because of ongoing symptoms. My endo said that we should stop blaming our thyroids for symptoms that are common in the population!

I would really appreciate your thoughts/advice.

9 Replies

Your Endo sounds a right muppet, he should find another job.

Read as much as you can on here, ask questions and don't rely on the NHS.


it is normal to reduce your levo when you add t3 x


Endo sounds a right plonker, get a new one who understands thyroid alot better!!! Your T3 should be on the high end of scale and T4 optimum too!! I take armour thyroid which contains t4 and t3 and I also take extra t4 as my body blocks it for some reason!! The Stop the Thyroid Book is fabulous, get one and go informed to your new endo, best of luck

1 like

Yes you have. Its a tiny amount of t3.

My endo told me I felt better because it was a placebo.... I said it wouldn't hurt to double the dose then! He did... But I no longer tae it.. I switched to self treating myself with NDT.

Xx. G


Sharon, Your endo has reduced your T4 too much. The T3/T4 ratio is 3:1. He should have reduced your T4 by 25mcg when adding in 10mcg T3.


T3 is three times stronger than T4 so you would think it would be usual to reduce levothyroxine in line with this i.e. 3:1 ratio. A study entitled, “The pharmacodynamic equivalence of levothyroxine and liothyronine: a randomized, double blind, cross-over study in thyroidectomized patients” confirmed this ratio -

However, there are several different methods for calculating the ratio of combined T3 and T4 to account for absorption and there have been several different studies using various different ratios and so it can get very confusing.

There are now European guidelines for the experimental use of T3 + T4 which show that the ratio should be between 14:1 and 17:1 depending on which method was used -

Therefore, on 100mcg T4, according to the guidelines, you should have around 6.25mcg T3. There isn’t a tablet of that strength so endos are told to give 10mcg.

This amount of T3 might work for you unless, of course, you have the faulty DIO1 gene, in which case you may well need more.

There is information about this gene and testing here:


Hi Lynn. I have had the genetic test and I am heterozygous which I believe is one faulty on done not. This is why I wanted to try T3 seeing that it is always on the low side when tested.


Hi SharonH, I think T3 will probably help you. Those with one faulty gene felt better and those with two felt much better. Do let me know how it goes.


You have on-going symptoms because you're not converting your T4 to T3. You need to take T3. It should be at the top of the range, not the bottom. Your endo doesn't know much about thyroid, does he!

Hugs, Grey


You may also like...