Advice on Results

[Fifi12]

Hi. I am looking for advice on blood test results.

TSH 0.13. (0.27-4.2)

FreeT3. 10 (3.1-6.8)

Free Thyroxine. 0.5 (12-22)

Thyroglobulin Antibodies. 33 <115

Thyroid peroxidase Antibodies. 25 <34

(I am T3 only. )

I was waking up with headaches , muscle / joint pain ,brain fog, feeling like I was walking through mud when on Levothyroxine. Now I am feeling so much better that I am not on it.

Any help will be much appreciated.

[SeasideSusie Remembering]

Fifi12

When did you take your last dose of T3 before the test?

The day before the test we should split dose into 2 or 3 and last dose should be 8-12 hours before the test, this gives a measure of the normal circulating amount of hormone.

If you took last dose as above then your FT3 result is a long way over range and suggests that you should lower your dose of T3.

If you took your last dose before the test then you have a false high result

[Fifi12 in reply to SeasideSusie]

I took my last dose at midnight, I didn’t know I had to split it though. My bloods were taken at 10.30am. The closest time I could get to 9.am

[SeasideSusie Remembering in reply to Fifi12]

Fifi12

Early blood draw only affects TSH level (gives higher TSH) and because you are taking T3 only your TSH is going to be low/suppressed.

Your FT3 might be slightly higher than if you'd split it, but I think it might still be suggesting overmedication and may be worth trying a slight reduction.

What dose of T3 do you take?

[Fifi12 in reply to SeasideSusie]

Thybon Hemming , 40 mcg

[SlowDragon Administrator in reply to Fifi12]

Suggest you retest

Day before test

Take T3 - 20mcg waking, 10mcg mid afternoon, 10mcg at 9pm

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

What vitamin supplements are you currently taking

[Fifi12 in reply to SlowDragon]

I think they were all last tested in 2019. I also take zinc and selenium, omega 3 and magnesium.

Do you think I should lower my dosage .

[SlowDragon Administrator in reply to Fifi12]

I would test first

Monitor My Health Is cheapest at £26.10

[Evej13 in reply to SeasideSusie]

SeasideSusie I have seen various timings for testing - some from 8 to 12 hours, others at least 15+ (mostly on Facebook forums). It seems to me the 15+ hours MIGHT be coming from STTM which I no longer follow. I have always tested as you and others here suggest - 8 - 12 hours if taking T3 (I'm on NDT, split dose 4x per day), 24 hour if T4 only treatment. Can you please explain to me why you say 8 to 12 hours so I can provide a good argument to those who are saying 15hrs+? Thanks!

[SeasideSusie Remembering in reply to Evej13]

Evej13

Nobody is going to agree on this, however many articles you read, whomever you speak to. Medical professionals don't even agree on it, some good endos tell their patients exactly the timing we say here, others say it doesn't matter. What does matter that however you take your medication for one thyroid test then ensure that you take it exactly the same for subsequent tests because the GP will be basing adjustment of dose on results, so you need them to be comparable every time to get the correct dose for you.

T3 has a half life of about 24 hours (and of course this may vary from person to person).

T3 peaks in the blood around 2-4 hours after ingestion (depending on which article you read).

So after the peak (let's say 4 hours) then the FT3 level will gradually start to fall. Due to the half life being 24 hours, we don't want to wait that long because there will only be 50% of the last dose left, and we don't want to measure at the peak of around 4 four hours, so it's a good idea to split the difference and measure half way between the two, which would be about 10 hours. Hence a window of 8-12 hours fits that bill and is what you will find that many experienced hypo patients on this forum will say.

[Evej13 in reply to SeasideSusie]

Perfect. Thank you. It seems to me from what you're saying here that consistency might be the most important thing then. This would also help with comparison between blood results and symptoms.

[Shazy-B]

Hi sorry to bombard you with questions but I’m really interested in your story….what were your labs were before going on T3? Who suggested coming off T4 and who prescribes your T3, how quickly did you start to feel better? Were any of your antibodies high before taking T3? Did you have any symptoms when you initially swapped over?

Sorry again for all the questions 🤦🏻‍♀️