Low TSH but feeling very well

[Hammyfish1]

Is it possible to have a TSH below range, mine was less than 0.005 mu/l ( 0.3- 5.6) and a normal free T4 of 9.9 ( 6.3-14) and for your thyroid to be working ok? I’m afraid my knowledge is limited despite trying to research the area. I feel really well and do not have any symptoms despite my GP insisting that I am hyperthyroid. Back in November/ December I definitely had symptoms and even up until recently I had mild symptoms but I now feel great. Does anyone have any clue what is happening. I have no other blood results. These are the latest from last Wednesday. Thanks.

[SlowDragon Administrator]

TSH is slow to respond to changes

Just testing TSH and Ft4 is completely inadequate if looking at possible Graves’ disease or Hashimoto’s

Important to test all thyroid antibodies for both Hashimoto’s and Graves’ disease.

Hashimoto’s frequently starts with transient hyperthyroid results

thyroiduk.org.uk/tuk/about_...

Link about thyroid blood tests

thyroiduk.org/tuk/testing/t...

For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12

Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies

Ask GP to test vitamin levels

You may need to get full Thyroid testing privately as NHS refuses to test TG antibodies if TPO antibodies are negative

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies

thyroiduk.org.uk/tuk/testin...

For thyroid including antibodies and vitamins

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

[Lienka]

Congrats! If you feel great don't change anything. TSH is compressed because of the medication you're taking. Are you taking T3? Your T4 in not hyper.

[Hammyfish1 in reply to Lienka]

Thanks Lienka, I’m taking carbimazole 15mg once a day. I was initially on 20mg but became neutropaenic and GP reduced it to 10mg and now white cell and neutrophils are ok it has been increased to 15mg.

[GKeith]

Your TSH is fine, it's your FT3 that you need to know. Your T4 is is a bit low but it doesn't matter either until and if you get your T3 results. Your FT3 actively circulates in your bloodstream and your Ft4 is an inactive ingredient whose only "job" is to turn into T3.

[Hammyfish1 in reply to GKeith]

Thanks, I now understand!

[GKeith in reply to Hammyfish1]

Glad to hear it; too many of us suffer needlessly. I hope you can get some T3. Peace be with you.

[Hammyfish1 in reply to GKeith]

And peace be with you GKeith!