Should I take my Levothyroxine before a blood test to check TSH?

[Thyroidenquiry]

Should I take my Levothyroxine before a blood test to check TSH?

[SeasideSusie Remembering]

Thyroidenquiry

If all that is being tested is TSH then taking Levo wont affect it, taking Levo affects FT4 level.

What does affect TSH is:

* Time of test - TSH is highest early morning and lowers throughout the day

* Eating - this can lower TSH

* Coffee - can affect TSH so water only before test

[Thyroidenquiry in reply to SeasideSusie]

Thank you. My blood test is at 1pm so I’ll just drink water but take my Levo as normal in the morning

[SeasideSusie Remembering in reply to Thyroidenquiry]

Thyroidenquiry

Does your GP adjust your dose of Levo by TSH? If so then to avoid a reduction, or to get an increase if you feel the need, then you need the highest possible TSH which you wont get at 1pm. Take a look at the first graph in this post which shows TSH levels throughout the day

healthunlocked.com/thyroidu...

A test at 1pm is going to give you possibly the lowest TSH of the day. Can you possibly rearrange your test for no later than 9am?

GP shouldn't be using TSH alone anyway, it doesn't give an indication of thyroid status, it's not a thyroid hormone, it's a pituitary hormone which tells the thyroid to make hormone when it detects there's not enough. It's FT4 and FT3 which are the thyroid hormones and these are what dose adjustment should be based on.

[Thyroidenquiry in reply to SeasideSusie]

Very helpful, thank you. I am having a blood test as I have been feeling very fatigued and achy for a few weeks. I will see if I can organise an earlier appt time

[SeasideSusie Remembering in reply to Thyroidenquiry]

Thyroidenquiry

Sounds like possibly you are undermedicated. See if your GP will test for FT4 (at least) and FT3 (if possible).

Also, because we need optimal nutrient levels for thyroid hormone to work properly, ask for the following to be tested:

Vit D

B12

Folate

Ferritin

Ferritin in particular can cause fatigue if low. Aches and pains (in muscles and joints) can be low Vit D.

When you have your results you are welcome to post them on the forum for comment. Ask the receptionist at your surgery (never the doctor) for a print out of your results, the reference ranges should also be on the print out and put the results/ranges in a new post.

Do you take a B Complex or Biotin supplement? If so leave this off for 7 days before the test.

[shaws in reply to Thyroidenquiry]

An early a.m. blood draw might get you the increase you feel you need. TSH drops throughout the day and may mean you don't get the increase you need.

[Thyroidenquiry in reply to SeasideSusie]

I have been on the same dose of Levo since diagnosed 11 years ago. 100mmg

[fuchsia-pink in reply to Thyroidenquiry]

I've had some success in getting the tests SeasideSusie has mentioned by saying that these are the tests recommended by Thyroid UK.

It is important to have proper testing if you don't feel fully well: us hypos tend not to do well on the nutrient front without supplementing - but you won't know if you're taking the right things unless you get the tests done. And please get your actual blood results rather than just being told they're that you;re "in range" or "normal" - you want better than that - you want optimal

[SlowDragon Administrator]

Just testing TSH is completely inadequate

Do you always get same brand of levothyroxine?

What vitamin supplements are you currently taking?

Suggest you rebook as an early morning appointment

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

About 90% of primary hypothyroidism is autoimmune thyroid disease

Ask GP to test vitamin levels, Ft4 and Ft3. (Plus thyroid antibodies if never had them tested at initial diagnosis)

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 .

Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).

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

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

List of private testing options

thyroiduk.org/getting-a-dia...

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Thriva Thyroid plus antibodies and vitamins By DIY fingerpick test

thriva.co/tests/thyroid-test

Thriva also offer just vitamin testing

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins by DIY fingerprick test

bluehorizonbloodtests.co.uk...

If you can get GP to test vitamins and antibodies then cheapest option for just TSH, FT4 and FT3

£29 (via NHS private service ) and 10% off down to £26.10 if go on thyroid uk for code

thyroiduk.org/getting-a-dia...

monitormyhealth.org.uk/

Also vitamin D available as separate test via MMH

Or alternative Vitamin D NHS postal kit

vitamindtest.org.uk

[Thyroidenquiry in reply to SlowDragon]

Currently taking vitamin D, zinc with copper and vitamin b complex as advised by nutrition doctor. I have re-booked blood test for 9am. I think they are testing T3 & T4 as well but will check. Helpful to consider private options to get more things tested. Auto anti-bodies tested years ago and raised. Yes Hashimotos

[SlowDragon Administrator in reply to Thyroidenquiry]

ESSENTIAL to stop any supplements that contain biotin a week before ALL BLOOD TESTS as biotin (in vitamin B complex) can falsely affect test results

So as you have Hashimoto’s are you on strictly gluten free diet?

Or dairy free diet?

How much vitamin D are you currently taking?

Important to retest vitamin D twice year

Other three vitamins, at least annually

[Thyroidenquiry in reply to SlowDragon]

Not on a gluten free or dairy free diet. What is the evidence for this please?

[SlowDragon Administrator in reply to Thyroidenquiry]

Many, many Hashimoto’s patients develop gluten intolerance due to leaky gut (or some research suggests it might be leaky gut that leads to autoimmune disease)

You do not need any obvious gut issues to be gluten intolerant

Hashimoto's frequently affects the gut and leads to low stomach acid and then low vitamin levels

Low vitamin levels affect Thyroid hormone working, hence why so many Hashimoto’s patients need vitamin supplements despite good diets

Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten. Dairy is second most common.

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps, sometimes significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies

While still eating high gluten diet ask GP for coeliac blood test first or buy test online for under £20, just to rule it out first

healthcheckshop.co.uk/store...?

Assuming test is negative you can immediately go on strictly gluten free diet

(If test is positive you will need to remain on high gluten diet until endoscopy, maximum 6 weeks wait officially)

Trying gluten free diet for 3-6 months. If no noticeable improvement then reintroduce gluten and see if symptoms get worse

chriskresser.com/the-gluten...

amymyersmd.com/2018/04/3-re...

thyroidpharmacist.com/artic...

drknews.com/changing-your-d...

restartmed.com/hashimotos-g...

Non Coeliac Gluten sensitivity (NCGS) and autoimmune disease

ncbi.nlm.nih.gov/pubmed/296...

The predominance of Hashimoto thyroiditis represents an interesting finding, since it has been indirectly confirmed by an Italian study, showing that autoimmune thyroid disease is a risk factor for the evolution towards NCGS in a group of patients with minimal duodenal inflammation. On these bases, an autoimmune stigma in NCGS is strongly supported

ncbi.nlm.nih.gov/pubmed/300...

The obtained results suggest that the gluten-free diet may bring clinical benefits to women with autoimmune thyroid disease

nuclmed.gr/wp/wp-content/up...

In summary, whereas it is not yet clear whether a gluten free diet can prevent autoimmune diseases, it is worth mentioning that HT patients with or without CD benefit from a diet low in gluten as far as the progression and the potential disease complications are concerned

restartmed.com/hashimotos-g...

Despite the fact that 5-10% of patients have Celiac disease, in my experience and in the experience of many other physicians, at least 80% + of patients with Hashimoto's who go gluten-free notice a reduction in their symptoms almost immediately.

[Thyroidenquiry in reply to SlowDragon]

Thank you. I clearly have lots more to investigate!

[SlowDragon Administrator in reply to Thyroidenquiry]

Come back with new post once you get results from GP

May need to get private testing if they won’t test everything

[greygoose in reply to Thyroidenquiry]

Currently taking vitamin D, zinc with copper and vitamin b complex as advised by nutrition doctor.

Did this nutriton doctor actually test your levels before advising that you take the supplements? Hypos usually have low zinc and high copper - as I'm sure you know, the two should be kept balanced - so taking extra copper is not advisable. I would want my copper tested, at least, before taking any, because excess copper is not a good thing.

Did he not also tell you to take magnesium and vit K2-MK7 withy your vit D? Because they all work together.

[Thyroidenquiry in reply to greygoose]

He did check my levels before advising yes. I am catching up with him again soon so will check regarding the copper (thank you). Vit D always from November through to March. No advice re Magnesium etc

[greygoose in reply to Thyroidenquiry]

Right, well, you might want to check up about the magnesium and vit K2 because they are very important. Taking vit d without magnesium won't give you good results because they need each other to work, and most people are deficient in magnesium.

As to the vit K2, it's necessary because taking vit D increases absorption of calcium from food, and the K2 makes sure it goes into the teeth and bones, and doesn't build up in the soft tissues, causing problems.

[Thyroidenquiry in reply to greygoose]

This is what I’m having tested

Blood test

[SlowDragon Administrator]

How long ago was previous blood test, do you have results you can add?

On levothyroxine TSH must be under 2. Most people, when adequately treated will have TSH well under one.

Median TSH graph of healthy population not on levothyroxine

healthunlocked.com/thyroidu...

TSH daily variation

healthunlocked.com/thyroidu...

Very important when in day you test TSH ....

researchgate.net/publicatio...

“According to the current TSH reference interval, hypothyroidism was not diagnosed in about 50% of the cases in the afternoon.”

“Further analysis demonstrated inadequate compensation of hypothyroidism, which was defined in 45.5% of the morning samples and in 9% of the afternoon samples”

ncbi.nlm.nih.gov/pubmed/252...

TSH levels showed a statistically significant decline postprandially in comparison to fasting values. This may have clinical implications in the diagnosis and management of hypothyroidism, especially SCH.

[Thyroidenquiry in reply to SlowDragon]

Thank you