Taking t3 and t4

[JJB21]

Hi I have been hypothyroid for 5 years tsh started at 60 and now down to 0.03 everything else re bloods is in line,i still have symptoms however not as severe endo suggested trying T3 and T4 . I was taking 150 levo so was told T3 5x stronger so using 25 levo and 25 T3 .just had some bloods results after 1 month on this and TSH IS 0.1 t4 gone down to 8 from 18.5 not had t3 done this time as GP wont do only endo. does my T4 sound right any advise please not back to see endo till July Thanks Julie x

[SeasideSusie Remembering]

JJB21

Can we have the reference ranges for your results please, so that we can interpret them accurately. Ranges vary from lab to lab.

I was taking 150 levo so was told T3 5x stronger so using 25 levo and 25 T3

What were your results before you added T3?

Levo reduced from 150mcg down to 25mcg in one go? T3 introduced at 25mcg rather than building up gradually from 1/4 tablet? If so your endo hasn't got a clue I'm afraid. Is the T3 prescribed on the NHS? Is your endo hoping your T3 trial will fail?

[JJB21 in reply to SeasideSusie]

before t3 added tsh 0.03range 0.35 -5.50

after t3 added 0.1tsh

T4 18.50 pre t3 range 10.00- 20.00

T4 after 8 .2

Not on trial I bought t3 on line via endo recommendation to try

thx

[SeasideSusie Remembering in reply to JJB21]

Was FT3 tested before suggesting you add T3? If not how on earth did your endo know whether or not you needed it? However, as your endo reduced your Levo from 150mcg to 25mcg, I doubt he has any idea about T3 at all. You might want to consider whether you wish to consider consulting with this endo.

[JJB21 in reply to SeasideSusie]

Thx

[jimh111]

Point yout endo to this ncbi.nlm.nih.gov/pmc/articl... . Liothyronine is about 3x as potent as levothyroxine. It may be 4x or 5x as potent in the blood but it has different absorption rates and half-life. Thus, the ratio you swallow is not the ratio you get in the blood. This is school kid stuff.

[JJB21 in reply to jimh111]

Thx

[MaisieGray]

JJB21 Well no, one isn't stronger than the other in the way that one beer might be said to be stronger than another. One is largely an inactive storage pro-hormone, the other an active hormone, separated by a single iodine atom, so they have different functions. For the purpose of interchanging their use, people do use a rough equivalency of 4:1, 3:1, or indeed anything else, Adding T3 to T4 does not automatically require a reduction in T4, it depends what were the levels of your FT4 and FT3 at the time. But certainly should not have led to a reduction of 150 to 25 mcg T4, that is absolutely inappropriate. Hence why your FT4 has plummeted. When taking T3 it is to be expected that both your TSH and FT4 will be lower, but pending sight of the reference range for that result, it looks as if the FT4 may now be below range, indicating that your dose of T4 is probably now too low for you.

[JJB21]

thx