sudden drop in tsh: I had bloods done last week... - Thyroid UK

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sudden drop in tsh

HoneyBee2 profile image
6 Replies

I had bloods done last week and expected them to be the same as the last bloods I had done because I feel no different, but my tsh has gone from 2.39 to 0.75 in 3 months with no changes to my levothyroxine, I only take 25mcg

Im just so confused about how it’s dropped so much, to the point where I feel like they might have switched my blood sample with someone else’s by accident

(Also they didn’t test my free t3 or free t4)

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HoneyBee2 profile image
HoneyBee2
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6 Replies
greygoose profile image
greygoose

Was the blood draw at the same time of day as the last one?

HoneyBee2 profile image
HoneyBee2 in reply to greygoose

the 2.39 one was at 9am and the 0.75 was 2pm and I didn’t take my levothyroxine before either

greygoose profile image
greygoose in reply to HoneyBee2

Well, there you are, then. That's why it appears to have dropped so suddenly.

TSH levels vary throughout the day. Highest around midnight, dropping slowly until 9 am, then dropping rapidly until around midday when it's at its lowest. It then starts to slowly rise again.

tattybogle profile image
tattybogle in reply to HoneyBee2

around 1-3pn is the lowest level of TSH in every day .

so , on the same day It is going to be higher at 9 am than it is at 2pm.

See this graph showing the TSH of 33 healthy people. (TSH is the black line)

Some people will have a bigger difference than this, and some will have smaller,

So the circadian rhythm of TSH explains at least some of the difference in your TSH results .

/
SlowDragon profile image
SlowDragonAdministrator

TSH will be at lowest after lunch

TSH has pronounced diurnal variation……highest in morning

ALWAYS test early morning, ideally before 9am, only drinking water between waking test and last dose Levo 24 hours before test

This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)

Just testing TSH is completely inadequate

Bloods should be retested 6-8 weeks after each dose change or brand change in levothyroxine

For full Thyroid evaluation you need TSH, FT4 and FT3 tested

Also both TPO and TG thyroid antibodies tested at least once to see if your hypothyroidism is autoimmune

Very important to test vitamin D, folate, ferritin and B12 at least once year minimum

Low vitamin levels are extremely common when hypothyroid, especially with autoimmune thyroid disease

About 90% of primary hypothyroidism is autoimmune thyroid disease, usually diagnosed by high TPO and/or high TG thyroid antibodies

Autoimmune thyroid disease with goitre is Hashimoto’s

Autoimmune thyroid disease without goitre is Ord’s thyroiditis.

Both are autoimmune and generally called Hashimoto’s.

Significant minority of Hashimoto’s patients only have high TG antibodies (thyroglobulin)

20% of autoimmune thyroid patients never have high thyroid antibodies and ultrasound scan of thyroid can get diagnosis

In U.K. medics hardly ever refer to autoimmune thyroid disease as Hashimoto’s (or Ord’s thyroiditis)

Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins

Post all about what time of day to test

healthunlocked.com/thyroidu...

Testing options and includes money off codes for private testing

thyroiduk.org/testing/

Medichecks Thyroid plus BOTH TPO and TG antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes BOTH TPO and TG antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

Only do private testing early Monday or Tuesday morning.

Link about thyroid blood tests

thyroiduk.org/testing/thyro...

Link about Hashimoto’s

thyroiduk.org/hypothyroid-b...

Symptoms of hypothyroidism

thyroiduk.org/signs-and-sym...

Tips on how to do DIY finger prick test

support.medichecks.com/hc/e...

Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee

BEFORE booking any private consultation absolutely ESSENTIAL to get FULL thyroid and vitamin testing

A) vitamin levels likely low and need improving

B) first consultation waste of time and money without full test results

C) extremely important to test correctly early morning

Come back with new post once you get results

Here’s link for how to request Thyroid U.K.list of private Doctors emailed to you, but within the email a link to download list of recommended thyroid specialist endocrinologists

Ideally choose an endocrinologist to see privately initially and who also does NHS consultations

thyroiduk.org/contact-us/ge...

SlowDragon profile image
SlowDragonAdministrator

What vitamin supplements are you taking

You know your hypothyroidism is autoimmune

Are you on dairy free and/or gluten free diet

Guidelines of dose Levo by weight

approx how much do you weigh in kilo

Standard STARTER dose Levo is 50mcg, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose of approximately 1.6mcg per kilo of your weight per day

pathlabs.rlbuht.nhs.uk/tft_...

Guiding Treatment with Thyroxine:

In the majority of patients 50-100 μg thyroxine can be used as the starting dose. Alterations in dose are achieved by using 25-50 μg increments and adequacy of the new dose can be confirmed by repeat measurement of TSH after 2-3 months.

The majority of patients will be clinically euthyroid with a ‘normal’ TSH and having thyroxine replacement in the range 75-150 μg/day (1.6ug/Kg on average).

The recommended approach is to titrate thyroxine therapy against the TSH concentration whilst assessing clinical well-being. The target is a serum TSH within the reference range.

……The primary target of thyroxine replacement therapy is to make the patient feel well and to achieve a serum TSH that is within the reference range. The corresponding FT4 will be within or slightly above its reference range.

The minimum period to achieve stable concentrations after a change in dose of thyroxine is two months and thyroid function tests should not normally be requested before this period has elapsed.

Some people need a bit less than guidelines, some a bit more

TSH should be under 2 as an absolute maximum when on levothyroxine

gponline.com/endocrinology-...

Graph showing median TSH in healthy population is 1-1.5

web.archive.org/web/2004060...

Comprehensive list of references for needing LOW TSH on levothyroxine

healthunlocked.com/thyroidu....

onlinelibrary.wiley.com/doi...

If symptoms of hypothyroidism persist despite normalisation of TSH, the dose of levothyroxine can be titrated further to place the TSH in the lower part of the reference range or even slightly below (i.e., TSH: 0.1–2.0 mU/L), but avoiding TSH < 0.1 mU/L. Use of alternate day dosing of different levothyroxine strengths may be needed to achieve this (e.g., 100 mcg for 4 days; 125 mcg for 3 days weekly).

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