400mcg a day since 16 years old : hi guys, I... - Thyroid UK

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400mcg a day since 16 years old

Strength96 profile image
10 Replies

hi guys,

I had a full thyroid removal when I was younger 16, severely overactive thyroid/ graves etc. After a long time of back and forth with testing, I was put on 400mcg (4x100mcg tablets a day) and have remained on that dose for 10 years. until recently. I’m now 26 and over the past few months, my GP (after seeing a pre op blood test) have been reducing my medication rapidly as my t3 and t4 were ‘very high’. I was jumped from 400 to 300 and now 200 with another test in 2 weeks time.

Latest results before the medication drop:

free t3 8.2

free t4 35.8

Is this very high?

After further investigation, it turns out that my doctors have not been carrying out tests for my t3 or t4 levels since 2016 just my TSH. So every time I have had a blood test or went in feeling unwell, my medication was never changed.

Couple of questions really….has anyone been on 400mcg before? As every time I ask someone they seem shocked that it is a very high dose.

Does anyone know if it’s normal for GPs to not test t3 and t4 despite them doing it at the start of my tests to get the correct dose.

Does anyone know if having really high t3/t4 for so long can cause serious side effects?

Any information I would really appreciate as I’m getting really confused with it all.

Cheers

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Strength96 profile image
Strength96
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10 Replies
Strength96 profile image
Strength96

400mcg Levothyroxine*

helvella profile image
helvellaAdministratorThyroid UK

It is a high dose. But you need what you need.

Very often high doses are required when there is an issue with absorption. But that is not necessarily the case.

I'm not shocked at your dose. But surprised that it hasn't previously been brought up as an issue.

Not sure where you are - UK? Patients in the UK have a right to copies of their records - and I suggest you ask for all your blood tests going back ten years. Make sure they include the reference intervals (ranges) as without them they are just numbers.

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PurpleNails profile image
PurpleNailsAdministrator

400mcg is a very high dose.

Was is definitely 4x 100mcg pills. Pills come in lower strength.

Do you take away from food inc hot drinks, medication & supplements.

A guide can be 1.6mcg x 1kg body weight. but this is just a guide. Roughly how much to you weigh?

If you can add range in results we can interpret accurate. Ranges vary between labs.

By most ranges, -yes- they are above ranges and you look ‘over medicated’ not hyperthyroid (you have no thyroid)

free t3 8.2

free t4 35.8

When you had Graves you likely had much higher level typically + FT4 40, FT3 15 as an example.

Often GPs go by TSH (thyroid stimulating hormone) only - which is pituitary Hormone (it signals thyroid to produce) it’s assumed if TSH is in range so will actually thyroid hormone.

You have no thyroid to produce and after being hyper the mechanism regulating this system is damaged so TSH becomes unreliable.

The TSH is usually affected by remaining low so even when levels of low it stays when I should rise. For it to appear in range when FT4 & FT3 are high is extremely unusual.

Any alterations should be gradual. Reduction of 25mcg per day and retesting after 6 weeks. So doctors has not stuck to this regimen and you may have symptoms caused by the sudden drop.

Do you remember time of blood test, if you’d eaten before & how long after dose the draw was taken.

Do you take any supplements?

Biotin (in high doses) can skew results often in a b complex or multi supplements.

Strength96 profile image
Strength96 in reply to PurpleNails

I usually fast until mid day, and always take my medication first thing when I wake up, I have black coffee sometimes about an hour to 2 hours after. I don’t take any other supplements with my medication.

It has always been 4x100mcg it says it on the packet and states 4 to be taken each day.

At my heaviest I was 130kg but have increased weight over the years from weight training 110kg - 125kg Currently I’m about 125kg but have struggled with training for quite some years covid onwards really.

Recently my doctors have not stuck to this regime as they have decreased by 100 and then another 100 over a 2 month period. I have never been told my ranges but will be asking for my medical history as the pervious comment suggest .

My blood tests are usually in the mornings and I don’t eat or drink before other than water. The draw would have been taken around 3/4 hours after my dose.

I don’t really take any supplements anymore, I did whilst training but haven’t really continued.

PurpleNails profile image
PurpleNailsAdministrator in reply to Strength96

Someone already muscular & burning energy with weight training would need a much higher dose - 400mcg might still be too high, but it would explain it.

As you train less now the hormone doesn’t get depleted in same way so thyroid levels might has risen.

Someone who is naturally petite and leads an inactive lifestyle wouldn’t require nearly as much hormone in their system.

Another possibility might be that when you were 16 doctors were using child ranges which are different to adult. Often child ranges are used until 18. Or infant - child - adult for example.

Have you had symptoms / feel improved from the reduction?

Having blood drawn 3/4 hours after dose shows FT4 at a peak level.

TSH is highest first thing in morning (just before 09.00). delaying dose until after draw or altering times to it’s taken 24 hours before draw will show lowest FT4. Which is what you want to know.

Doctors often say timings are not relevant, but it may be the difference between being in range or outside of range.

Are you in UK? Some practices offer online access to records, very useful - if not obtain printed copies with ranges. Verbal or hand written copies are not to be accepted as often inaccurate.

Nutrients can often be affected by abnormal thyroid levels. Has folate, ferritin, B12 and vitamin D been tested?

Out of interest how was your Graves managed when diagnosed. Were you taking antithyroid medication before surgery?

Doctors do not like levels over range for long time as it can affect heart & bones. This is based on patients with prolong untreated very high hyper levels.

Ask for ECG and bone density scan, have them explain why if it’s not necessary.

Do you know if heart rate has been fast in past?

jimh111 profile image
jimh111

These are high levels and they can be harmful. Your fT3, fT4 show that you are absorbing the levothyroxine. The interesting point is that you suggest your TSH has been normal, this leads to three questions.

Do you know your blood test results from when you were diagnosed?

What is your latest fT3, fT4, TSH (all three)?

How do you feel on the lower dose?

SlowDragon profile image
SlowDragonAdministrator

My blood tests are usually in the mornings and I don’t eat or drink before other than water. The draw would have been taken around 3/4 hours after my dose.

Thyroid tests should always be done early morning, ideally just before 9am and last dose levothyroxine 24 hours before test

So if you took levothyroxine before blood test the Ft4 is falsely high result

However Ft3 looks high

What’s the range on Ft4 and Ft3

What vitamin supplements are you currently taking

When were vitamin D, folate, ferritin and B12 levels last tested

Vitamin levels need testing at least once a year

Vitamin levels are likely to drop if levothyroxine dose is being reduced

Which brand of levothyroxine are you currently taking

Do you always get same brand levothyroxine at each prescription

Many people find different brands are not interchangeable

Test FULL thyroid and vitamins 8-10 weeks after any dose reduction

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

List of private testing options and money off codes

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

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

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/

NHS easy postal kit vitamin D test £29 via

vitamindtest.org.uk

pennyannie profile image
pennyannie

Hello Strength and welcome to the forum :

All this confirms and highlights to me is that the NHS testing of just a TSH is a total waste of time and money as once on any form of thyroid hormone replacement you need to monitor and dose of T3 and T4 levels.

I am Graves post RAI thyroid ablation in 2005 and became very unwell some 10 years later - see profile if interested.

I was refused a T3 and T4 blood test by my surgery and then, when I refused to leave the room, it was agreed I could have this blood draw if I paid the NHS laboratory - who sent me a bill for £34. something - but it showed a total imbalance between my T3 and T4 and my research continued as I was then told I was very lucky to have any T3 at all ???

Once a Graves patent - always a Graves patients - as we are looking at an auto immune disease for which there is no cure, and it's likely that your bloods will have Graves antibodies circulating which can ' sit on ' the TSH receptors sites distorting TSH readings for life.

Once you have ' lost ' your thyroid to either surgery or RAI the HPT axis on which the TSH reading relies is broken as the Hypothalamus - Pituitary - Thyroid feedback loop is not a closed any longer as the Thyroid isn't there any longer to close this circuit.

It seems to me doctors just refer to the computer dogma and have no understanding of basic physiology and the computer has no joined up thinking and doesn't know anything about the patients medical history.

Years ago when people were medicated to be well and not a blood test we do know that doses double those of which are now seen as ' normal ' were frequently prescribed.

With the current guidelines and thinking the majority of hypothyroid patents tend to be under medicated and kept non optimal as this generally means additional prescriptions for other health issues that tend crop up !!

Ok - soap box rant over :

So, you will learn here, how to take your thyroid hormone replacement, how your vitamins and minerals especially those of ferritin, folate, B12 and vitamin D play a vital role in maintaining core strength and assist in the conversion of T4 to T3 and generally how to go forward better placed to become your own best advocate on your thyroid health and management of same.

What happened for this massive reduction in medication, did the surgery change hands and the new broom sweep in and plug in the computer ?

HowNowWhatNow profile image
HowNowWhatNow

It seems a lot of thyroid patients are having their doses looked at and reduced in these last 2 months. Odd that GPs are all at once waking up.

Do you mind telling us what your op was? I wonder if in any way related to the high thyroid levels is why I ask. Hope it goes / went well.

These last 10 years - how have you felt, on the whole? Would you say you’ve felt overmedicated?

Omze profile image
Omze

HelloMany , many patients with graves need high dose thyroxine after thyroidectomy or RAI

Many patients of graves have thyroxine resistance and have latent thyroxine resistant, that's why they develop thus graves disease

Graves patient always need t4 higher than upper limit as there is resistance and they feel well when they cross the so called upper limit

If u r taking 400 mcg ur absorption is good as 400 is almost equal vent to 35 t4

The thing u do is shift to 50 mg of thyroxine tablet and ull get the same t3 like greater than 6.5 , with a t4 dose of approx 250 mg

Kindly discuss this with ur Gpe

HtH

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