I was diagnosed as having an underactive thyroid in March with a TSH >100 which I am currently being treated with 150mcg levothyroxine. I got a print out of all my previous blood tests I've had done over the years and back in 2005 it shows that I was just overactive with a TSH 0.37 (0.4-5.0) has anyone else had this or knows what it means? (If anything)
Has anyone else been over active without knowin... - Thyroid UK
Has anyone else been over active without knowing then years later become under active?
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It is not uncommon for people with Hashimoto's to have had times where TSH is a touch on the low side. Indeed, variations can occur in people over the years, have a look at this table:
Table 1. Presentations of Hashimoto’s Thyroiditis
Euthyroidism and goiter
Subclinical hypothyroidism and goiter
Primary thyroid failure
Hypothyroidism
Adolescent goiter
Painless thyroiditis or silent thyroiditis
Postpartum painless thyrotoxicosis
Alternating hypo- and hyperthyroidism
thyroidmanager.org/chapter/...
Have you been tested for Thyroid Peroxidase antibodies or Thyroglobulin antibodies?
Rod
No Rod, there is nothing on my printout of either of those being tested. Do you think I should ask for them to be done on my next bloods? x
Well unless you have something else going on, it does seem likely that you have autoimmune thyroid disease in the form of Hashimoto's - and a positive TPO antibody test is a strong indicator of that. Around 80% of hypothyroid people in the USA and the UK seem to have Hashimoto's - so it is pretty common. Knowing it can sometimes help to explain some of the oddities.
Rod
Hi personally l don't think that you were overactive at that tsh of 0.37. A lot of healthy people have a tsh of under 1, and different labs have different ranges. Did you feel hyper back then? You may have been hyper but maybe that was your "normal" tsh.
Jo xx
I have just been diagnosed with Graves Disease have had tsh readings o.94_1.2.I have had severe symptons of hyper,lost 5 kgs now waiting on more tests results Have started on gluten free diet& low iodine.I was only taking 50mcgs Eutroxsig.I know now Tsh tests are unreliable as it has taken 5 mths of hell for a holistic Gp to listen to me.meignore Tsh