Blood test after adding t3: If it takes 6-8 weeks... - Thyroid UK

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Blood test after adding t3

Hannah9 profile image
13 Replies

If it takes 6-8 weeks for levo to show full effect on blood tests when the half life is 7 days wouldn't blood test show full effect of t3 after like 16-24 days if the half life is 24 hours?

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Hannah9 profile image
Hannah9
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13 Replies
Hillman51 profile image
Hillman51

Hi , I am new to this , keep seeing T3 mentioned what does this mean, I,ve been on Levo for 6 weeks, just had a blood test and was told its 7.1....... But what is 7.1 !!!! 😳

Marz profile image
Marz in reply to Hillman51

Probably the TSH. Always ask for copies of ALL your blood test results with ranges so you can monitor your OWN health and see what the GP has missed. Seems they have omitted to test the FT4 - FT3 and thyroid anti-bodies TPo & Tg. For more understanding please read the main website connected to this Forum ....

thyroiduk.org

SlowDragon profile image
SlowDragonAdministrator in reply to Hillman51

Always ask for copies of your results including ranges

Presumably you have had dose increased if TSH is 7.1

Retesting after 6 weeks again

Always take Levo on empty stomach and then nothing apart from water for at least an hour after. Many take on waking, but it may be more convenient and possibly more effective taken at bedtime

verywell.com/should-i-take-...

Many people find Levothyroxine brands are not interchangeable. Once you find a brand that suits you, best to make sure to only get that one at each prescription.

All thyroid tests should be done as early as possible in morning and fasting and if taking Levo don't take it in the 24 hours prior to test, delay and take straight after.

Hillman51 profile image
Hillman51 in reply to SlowDragon

I have to see the doctor tomorrow to discuss what's next, I,m only taking 25mg every other day at the mo. The day of my blood test I didn,t take it before the test....... The trouble is you get told you have under active thyroid , but not told anything about it !!!

SlowDragon profile image
SlowDragonAdministrator in reply to Hillman51

That's because unless GP has thyroid issues themselves or knows someone well with it they have little idea how dreadful it can be when bloods are only slightly off

25mcg only every other day is a very very small dose.

And a TSH of 7.1 is a lot more than slightly off!

Ask for vitamin D, folate, ferritin and B12 tested. Important that these are optimal not just within range

Always get actual results and ranges on all blood tests

Hillman51 profile image
Hillman51 in reply to SlowDragon

I,ll find out tomorrow, if it is myTSH that's 7.1, I was told it should be 5 or under, do you know if that is right ?

SlowDragon profile image
SlowDragonAdministrator in reply to Hillman51

That sounds like TSH

Range typically (0.5 -4.8) but each lab varies slightly which is why always need ranges as well as test results

Many GP's mistakenly think anywhere within range is good enough, but a good endo or GP recognises we need dose of thyroxine high enough to push TSH down near, or slightly under, one. FT4 towards top of its range.

If you don't know already, ask if you have high thyroid antibodies. If GP hasn't tested, ask that antibodies are tested.

If antibodies are high this is autoimmune thyroid disease- 90% of hypothyroidism is due to autoimmune.

Dr's think it irrelevant, but essential to know

Hillman51 profile image
Hillman51 in reply to SlowDragon

Thanku for your help😊😊

Jaqs2017 profile image
Jaqs2017 in reply to SlowDragon

Hi SlowDragon , quite new to this site and trying to get my head around things and don't want to take you off the thread...I keep reading about Hashimotos....wondering why it is essential to know if treatment is the same, how you would know, all o recall seeing when I was diagnosed seven years was I have acquired, having problems at the mo and waiting for GP to call me later today? Thank you for your help, hope you have a good day ☆

SlowDragon profile image
SlowDragonAdministrator in reply to Jaqs2017

If antibodies are high this is Hashimoto's, (also known as autoimmune thyroid disease). About 90% of hypothyroidism in UK is due to Hashimoto's.

Hashimoto's very often affects the gut, leading to low stomach acid, low vitamin levels and leaky gut.

Low vitamins that affect thyroid are vitamin D, folate, ferritin and B12. If they are too low they stop Thyroid hormones working. Have these been tested, if not ask that they are.

Always get actual results and ranges on all blood tests

The reason you need to know if it's Hashimoto's is that very likely hidden food intolerances can be causing issues, most common by far is gluten.

Changing to a strictly gluten free diet may help reduce symptoms. Very, very many of us here find it really helps and can slowly lower antibodies.

Just don't be surprised if your GP is unaware of gut and gluten connection to Hashimoto's

thyroidpharmacist.com/artic...

thyroidpharmacist.com/artic...

amymyersmd.com/2017/02/3-im...

chriskresser.com/why-changi...

scdlifestyle.com/2014/08/th...

Jaqs2017 profile image
Jaqs2017 in reply to SlowDragon

Thank you for your response, it's really interesting, I have had stomach problems/IBS for around 20 years x

SlowDragon profile image
SlowDragonAdministrator

The six week test is because the rest of the Endocrine system and metabolism has to rebalance after dose change

Hannah9 profile image
Hannah9 in reply to SlowDragon

Ok, thank you

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