TSH has dropped to 0.01- what do I do about it?

[Qwerty11]

Good afternoon,

I had a postnatal thyroid bloods check this week (baby is 5 months- and I was shocked to see TSH has come back at 0.01 (range 0.2-5). This was taken mid morning, no fasting, just a routine blood test. My levothyroxine dose has not been reduced since it went up to cope with pregnancy. I am guessing I am taking too much levo and need to see GP? My blood test has been “passed” as in I haven’t been called to see them, but that does look very low. They only did TSH so I know maybe I should ask for T3 T 4 bloods too? I should add I feel really good at the moment, apart from no sleep with baby!

To give a reference point, these were my levels at the start of December, Results were:

TSH 0.957 mIU/L (0.27 - 4.20

pmol/L)

FREE THYROXINE

17.3 (12.00 - 22.00

pmol/ L)

FREE T3 4.98

(3.10 - 6.80

IU/mL)

THYROGLOBULIN ANTIBODY

24.8 (0.00 - 115.00

IU/mL)

THYROID PEROXIDASE ANTIBODIES*83.7 (0.00 - 34.00)

Thank you!

[Mary-intussuception]

I have no experience of dose during pregnancy and post natal but generally speaking - how do you feel? Because those results in December look ok to me, certainly Frees are not too high. I understand that TSH drops and varies throughout the day anyway and not enough on its own to be considering changing dose.

You have Hashimoto's so bloods can fluctuate. If you had TSH test now it would probably be different again.

If I had those FT4 and FT3 results just 3 months ago I wouldn't want you reduce my dose. What time of day were the December bloods taken?

[Qwerty11 in reply to Mary-intussuception]

That’s partly my worry, if I need to investigate more I will go to gp, but if I just stay away they will keep renewing current dose, which I have to admit I feel great on-despite getting very little rest these days I am coping with getting up Far too many times in the night etc! Thanks for speedy reply x

[Mary-intussuception in reply to Qwerty11]

If you feel great on present dose I wouldn't be querying it ! Certainly not looking for a lower dose!

If your FT3 and FT4 dropped any lower than December result you would be under-replaced.

[Qwerty11 in reply to Mary-intussuception]

Thanks again x

[a-g-g-8]

Are you taking a supplement or multivitamin containing biotin? This will make your TSH come up lower than it actually is. Just a thought!

[Qwerty11 in reply to a-g-g-8]

Wow do you know yes i am- just been to check the box of breastfeeding multivitamin...thank you v much for the info!

[a-g-g-8 in reply to Qwerty11]

Biotin can make your TSH look hypER, when in fact it's normal. This is well known in scientific literature, and my NHS endocrinologist told me too. But your GP might not be aware. Stop taking biotin for at least a week before your next thyroid test (as others have recommended, the private pin-prick home tests are great).

[Qwerty11 in reply to a-g-g-8]

I would never have picked up on this connection- thanks again!

[a-g-g-8 in reply to Qwerty11]

You're welcome

[MaisieGray in reply to a-g-g-8]

Just to clarify, biotin may skew some tests but not all, and how the results of thyroid function tests will be affected, can vary. Many, albeit not all, immunoassays contain biotin, and large amounts of biotin in a blood sample can interfere with the assay process of those containing biotin, skewing the results to be either falsely high or falsely low. In the case of competitive immunoassays usually used for low molecular weight targets such as T4, T3, and Cortisol, biotin interference causes a falsely high result, whereas in immunometric (sandwich) assays, it gives a falsely low result. Other characteristics of the assay can also make a difference, because for instance, a longer incubation time increases the opportunity for interference, and different assays for various analytes, even from the same manufacturer, can therefore vary in their susceptibility to biotin interference. So in one laboratory, the FT4 and total T3 assays might use a biotin-streptavidin fluorescent detection system, and biotin can cause falsely elevated results for those, but the TSH and total T4 assays won't be affected. In another, biotin can lead to falsely low TSH results, but FT3 and FT4 tests won't be affected. Biotin can also cause a lab’s assay for thyrotropin receptor antibodies to be falsely positive, which could lead to a misdiagnosis of Graves'.

[SlowDragon Administrator]

Suggest you get FULL Thyroid and vitamin testing privately

Then you can asses if dose needs slight reduction

Your high antibodies confirm you have Hashimoto's. Low vitamins are very common with hashi

You might be low in ferritin, B12, folate or vitamin D

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

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). 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 or all vitamins

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

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

Come back with new post once you get results

[Qwerty11]

Thanks i will arrange a private test- i did have low folate and low ish vit D last time i did a private test, so i was going to sort one about spring time, hoping things have improved.

[Mary-intussuception in reply to Qwerty11]

I noticed your LOW Folate, and wondered why you hadn't been prescribed during pregnancy. But looking back at previous posts - your Folate was in range ?

Also, looking back at earlier posts, after your GP or Endo had treated you for Vitamin D deficiency, I thought they should have kept you on a daily maintenance dose for life.

[Qwerty11 in reply to Mary-intussuception]

Hi, yes I was prescribed folic acid when pregnant, and I take vitamin D supplement- one i buy, not one GP will prescribe. I will get a repeat of the private test for thyroid plus vit and minerals, see what that shows, & come vack to this forum with the results. Many thanks all again! X

[Mary-intussuception in reply to Qwerty11]

Your welcome. But, as you feel good, is there any need to rush into more tests soon? Just a thought.

[Qwerty11 in reply to Mary-intussuception]

Im feeling fine, a million miles better than 3 years ago, and these days i have a baby to look after too... so yep its a good point, ill wait a bit. Ive gotto watch spending as im on mat leave too x

[crmavb]

I wouldn’t change your medication. If you were tested without warning, so no fasting and no stopping of medication then that also will effect your results. There’s so much pressure on you with a new baby. It’s wonderful that you feel well. If you start to get a fast pulse, loose stools, grinding your teeth, I would be guided by those signs to slightly lower medication.