Thyroid UK
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Hi my TSH is non existent has not been present for 2 years now. I was on NDT 120 mg for several years and but my FT4 fell of the charts (low range) and I did not feel good - my TSH was also really low (below range- when my Dad died my thyroid went whacky) anyways so as an experiment I tried synthroid - I guess I'm a good converter from T4 to T3 as my results are:

TSH A <0.01 range 0.32-5.04 mU/L

T4 Free 14.7 range 10.6-19.7 pmol/L

T3 Free 4.82 range 3.00-5.90 pmol/L

This is the first time in many years I've felt ok... but my doctor has now dialled back the synthroid dose from 175 ug to 150 ug ... my thyroid really hurts..

I've not had a TSH reading for a few years now (below range) and the ultrasound looks like a Swiss cheese.. anyways...I want after 1 week on 150 ug to go back up to 175 ug... as My thyroid hurts - I'm scared to go hypo again as that sucks- I don't feel hyper- but am also interested to see ( after 6 months on synthroid) if I would get a TSH reading..

Any thoughts ? Thankyou

2 Replies

The TSH is irrelevant once you are on thyroid hormone replacement, unless it goes high. It doesn't matter how low it goes, and your doctor should not be dosing by the TSH - as he obviously is if he wants to reduce your dose with those results! A low TSH does not automatically mean you are over-medicated, the most important number is the FT3.

Yes, you are converting well, according to those results, but there is still room for an increase in dose, if you feel you need one. You certainly don't need a reduction. Your doctor is uneducated in thyroid, like most of them!


Is there journal articles explaining why our TSH is non existent? That would be helpful to educate our Doctors. Thankyou and I do feel well for the first time in many years.


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