Thyroid bloods: Hi Since 2002 My various GPs go... - Thyroid UK

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Thyroid bloods

Cookienoodles profile image
8 Replies

Hi

Since 2002 My various GPs go through the ritual of insisting on an annual blood test and stopping my prescription until I have one. I've over replaced my thyroxine for all this time because I originally did not respond to thyroxine levels I was prescribed . Long story, but until I over replaced I was bed ridden for 2 years.

I dont worry about the over replacement. I accept that I need to do so to function. I have no symptoms of an overactive thyroid. My new GP has panicked, as usual, on seeing the blood test results. I asked for a copy because she has made me anxious. What do people think? Is this really that abnormal?

Free T4 19.6

TSH 0.01

Serum sodium 139, serum potassium 4.4, serum creatinine 55. Electrolytes normal.

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Cookienoodles profile image
Cookienoodles
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8 Replies
SeasideSusie profile image
SeasideSusieRemembering

Cookienoodles

Because reference ranges vary from lab to lab, you need to provide the ranges that came with your results.

We know that your TSH is suppressed but we have no idea whether your FT4 is over range. It would be with my surgery's range (7-17) but we also see on the forum 9-19, 11-23, 12-22 and others.

I expect your GP is panicking about the TSH, most doctors only use the TSH to adjust dose, which is wrong. TSH is not a thyroid hormone, it's the FT4 and FT3 which are the thyroid hormones and you are only overmedicated if FT3 is over range, and that's the one test they rarely do.

Cookienoodles profile image
Cookienoodles in reply to SeasideSusie

Ah thanks...

Free T4 19.6 9.00-19.10 pmol/L

Serum TSH 0.01 0.30-4.40 mU/L

SeasideSusie profile image
SeasideSusieRemembering in reply to Cookienoodles

OK, so your FT4 is slightly over range as well which, together with your suppressed TSH would suggest overmedication.

However, we also need FT3 to complete the picture.

T4 is a storage hormone which converts to T3. T3 is the active hormone that every cell in our bodies need.

It's possible that you may need a high FT4 to produce a decent amount of T3.

If you are still symptomatic it may be that you are not producing enough T3. Testing FT3 at the same time as FT4 will show whether you convert well enough or not.

Good conversion requires optimal nutrient levels so it's essential to test:

Vit D

B12

Folate

Ferritin

as well as

TSH

FT4

FT3

If your GP can't or wont do all of them you may wish to consider doing what hundreds of us here do and that is a private test with one of our recommended labs. Either of the following would be suitable, they are very similar, and either can be done by fingerprick or by venous blood draw at extra cost:

Medichecks Thyroid Check ULTRAVIT medichecks.com/thyroid-func...

You can use code THYROIDUK for a 10% discount on any test not on special offer

or Blue Horizon Thyroid PREMIUM GOLD bluehorizonbloodtests.co.uk... (previously known as Thyroid Check Plus Eleven)

Both tests include the full thyroid and vitamin panel. They are basically the same test but with the following small differences: For the fingerprick test: Blue Horizon requires 1 x microtainer of blood (0.8ml), Medichecks requires 2 x microtainers (total 1.6ml) Blue Horizon includes Total T4 (can be useful but not essential). Medichecks doesn't include this test. B12 - Blue Horizon does Total B12 which measures bound and unbound (active) B12 but doesn't give a separate result for each. Medichecks does Active B12. Total B12 shows the total B12 in the blood. Active B12 shows what's available to be taken up by the cells. You can have a reasonable level of Total B12 but a poor level of Active B12. (Personally, I would go for the Active B12 test.)

Blue Horizon include magnesium but this is an unreliable test so don't let this sway your decision, it also tests cortisol but that's a random cortisol test and to make any sense of it you'd need to do it fasting before 9am I believe.

When doing thyroid tests, we advise:

* Book the first appointment of the morning, or with private tests at home no later than 9am. This is because TSH is highest early morning and lowers throughout the day. If we are looking for a diagnosis of hypothyroidism, or looking for an increase in dose or to avoid a reduction then we need TSH to be as high as possible.

* Fast overnight - have your evening meal/supper as normal the night before but delay breakfast on the day of the test and drink water only until after the blood draw. Eating may lower TSH, caffeine containing drinks affect TSH.

* If taking thyroid hormone replacement, last dose of Levo should be 24 hours before blood draw, if taking NDT or T3 then last dose should be 8-12 hours before blood draw. Adjust timing the day before if necessary. This avoids measuring hormone levels at their peak after ingestion of hormone replacement. Take your thyroid meds after the blood draw. Taking your dose too close to the blood draw will give false high results, leaving any longer gap will give false low results.

* If you take Biotin or a B Complex containing Biotin (B7), leave this off for 7 days before any blood test. This is because if Biotin is used in the testing procedure it can give false results (most labs use biotin).

These are patient to patient tips which we don't discuss with doctors or phlebotomists.

Cookienoodles profile image
Cookienoodles in reply to SeasideSusie

That makes sense. She probably would test for T3 if asked.

I used to take liothyronine because thyroxine had no effect on me and I was diagnosed with CFS. I saw the late Dr Skinner.

A few years ago I was persuaded by a CFS specialist to go back to thyroxine because I was getting heart palpitations and sweats. These resolved when I went back onto thyroxine but I needed to take 225mcg to function. I put on weight, no longer have sweats or heart palpitations, pace and plan my energy, but much improved.

Just frustrating that I go through this each time I see another GP.

shaws profile image
shawsAdministrator in reply to Cookienoodles

Dr Skinner is greatly missed as I think he was the 'last' of doctors who treated the symptoms patients had, instead of only going by blood test results and adjusting willy/nilly.

Nanaedake profile image
Nanaedake in reply to Cookienoodles

If in the UK, the GP may request FT3 and then the lab doesn't do it. There are some thyroid guidelines on the NICE website. I seem to recall they advise testing FT3 in the case of thyrotoxicosis but not sure if that includes potential overmedication? You could check the guidelines. If they were my results I would be inclined to refuse to reduce thyroxine until FT3 was measured and would likely refuse to reduce if its in range unless there were other specific factors to take into account.

FT4 indicates the amount of thyroid hormone stored and free to use but not the active hormone available, or so I've read.

As Seasidesusie suggests, you can get them all checked through reliable online labs anyway.

Cookienoodles profile image
Cookienoodles in reply to SeasideSusie

What you say about B12 is interesting. I was diagnosed with b12 deficiency in 2000. Had to shift from 3 to 2 monthly injections because the gap was too long. I also had some success cutting out gluten.

Marz profile image
Marz

As your T3 was not tested your GP cannot insist you are over medicated. It is possible you are not converting the Inactive T4 into the Active T3.

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