T3 only: What blood tests should be done when on... - Thyroid UK

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T3 only

Chrys profile image
17 Replies

What blood tests should be done when on T3 only, and what sort of results should I look for? Paul Robinson says FT3 is the one that matters, but even then is not definitive.

My wife, who does not convert T4 well, if at all, has now been on 15mcg per day (3 lots of 5mcg) for some 5 weeks now, and I am concerned that this may be too low a dosage given that she has not improved much since stopping T4 altogether. The problem now is, as NHS GP's are unable to prescribe T3 unless approved by Endo's, I am concerned that it may be difficult getting dosage alterations. We are seeing the GP tomorrow, but am not optimistic that we will get a useful answer.

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Chrys
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17 Replies
waveylines profile image
waveylines

What dose of levothyroxine was she on before moving across to T3? Roughly speaking T3 is considered four times the stength of T4 so roughly speaking 15mcg of T3 is 60mcg of levothyroxine.

If she hasnt been converting well then the levothyroxine wil have backstacked in her sytem. T3 has to be introduced slowly like all thyroid meds, tiltrated gradually upwards normally in 6-8 weeks steps.

I expect your GP will want further advice from the endocrinologist as they are not experts in T3. It has to be under written by a specialist. When is your wife due her next appointment?

Blood tests would normally be TSH and Ft4 though the labs may agree to ft3 as your wife is on t3 only. Generally you would expect the ft4 to drop, the ft3 needs to be in range but can fluctuate followong taking it as its effects are more immediate so its important she does not take it on the morning of the test.

Paul Robinson has a facebook group so it might well be worth joining to talk to others on t3 only.

Hope this helps.

Chrys profile image
Chrys in reply towaveylines

Thanks WL, she was on 25mcg T4 and 15mcg T3 before stopping T4 altogether about 4 weeks ago.

SlowDragon profile image
SlowDragonAdministrator

You need full private blood test for thyroid and vitamins before changing dose

But she seems to be on tiny dose

Normally that kind of dose of T3 is in addition to 100mcg Levothyroxine

Is she Heterozygous or homozygous DIO2?

It usually doesn't mean we can't convert, but that we also need small dose of T3 alongside Levo

Conversion usually improves quite a lot once T3 is added and gut function improves

What were her last vitamin D, folate, B12 and ferritin results and ranges?

Exactly What supplements does she take?

And presumably she has Hashimoto's, so is she on strictly gluten free diet? Very often helps or is essential, especially on T3

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 Thyroid antibodies are raised

All thyroid blood tests should ideally be done as early as possible in morning and fasting. This gives highest TSH and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

T3, make sure to take last 5mcg dose exactly 12 hours prior to test

Private tests are available. Thousands on here forced to do this as NHS often refuses to test FT3 or antibodies

thyroiduk.org.uk/tuk/testin...

Medichecks Thyroid plus ultra vitamin or Blue Horizon Thyroid plus eleven are the most popular choice. DIY finger prick test or option to pay extra for private blood draw. Both companies often have special offers, Medichecks usually have offers on Thursdays, Blue Horizon its more random

Chrys profile image
Chrys in reply toSlowDragon

Is she Heterozygous or homozygous DIO2? Heterozygous

What were her last vitamin D, folate, B12 and ferritin results and ranges?

9 Sept while on 25mcg T4 and 15mcg T3:

Vit D 89.9 (50-200)

Folate 19.98 (2.91-50)

Active B12 131(25.1-165)

Ferritin 82.7 (13-150)

Supplements:

Vit D3 1400iU

Vit K2

Vit B Complex

Vit E 400iU

Omega3

Beta carotene

VitC 1000mg

Magnesium 150Mg

Zinc Carnosine

Selenium 200uG

Betaine HCL+Pepsin

Gluten free diet

Test on 25/10

TSH 0.382 or 0.28 (2 tests 1 NHS 1 private on same day!)

FT4 11.40 (0.27-4.2)

FT3 6.88 (3.1-6.8)

TPO 229 (00-34)

TG 991 (00-115)

We have had many private tests done in the past few years, mostly posted on here.

I am currently concerned about the T3 dosage, and worryingly low back pain and stomach pain, (also the usual GI problems suffered due Hashi's), which I hope does not indicate adrenal problems. GP visit tomorrow to report.

SlowDragon profile image
SlowDragonAdministrator in reply toChrys

Her results are extraordinary considering how little she is taking

Her vitamin levels look good. Vitamin D may be better around 100nmol. 1400iu is not a very high dose. Many of us need more than this as maintenance dose (personally I take 4000iu daily)

How long before the test on 25/10 had she taken her Levothyroxine and T3 ?

Advice is 24 hours prior to test for Levo and 12 hours prior for T3

Adrenal pain that I get, if I don't take my T3 every eight hours, is like an extremely sharp hot needle in each adrenal gland (top of kidneys).

I am Heterozygous too. Numerous tests over the years, including pheochromacytoma, pituitary function, pituitary tumour, MS, brain MRI etc etc

Have you considered dairy intolerance?

What brands of Levothyroxine and Liothyronine are you using?

Presumably you have tried different brands

Chrys profile image
Chrys in reply toSlowDragon

We have recently tested ok for dairy, although for the last two years have assumed lactose intolerance. T4 was Wockhardt for 2 years then Teva for one month. Still not tolerated.

T3 is Sigmapharm.

Chrys profile image
Chrys in reply toSlowDragon

No T4 or T3 for 24 hours prior test.

SlowDragon profile image
SlowDragonAdministrator in reply toChrys

Has she had an ultrasound scan of thyroid?

Multi nodular goitre can cause autonomous nodules chucking out Thyroid hormones regardless of TSH

Prof Toft talked about this in recent talk

Chrys profile image
Chrys in reply toSlowDragon

No, but I do intend to ask for more tests tomorrow.

SlowDragon profile image
SlowDragonAdministrator in reply toChrys

mobile.twitter.com/hashtag/...

About 17minutes into the main, most watched video

Chrys profile image
Chrys in reply toSlowDragon

I'm unable to find that video. All I can see is a lot of replies to a twitter thread. I am clearly missing out as I don't do Facebook or Twitter, Instagram or the myriad other sites which have proliferated in the last few years.

As expected, we have been referred back to the Endocrinologist for T3 adjustment and adrenal and other tests, which unless we pay - again- will take a further 3 months or so.

Chrys profile image
Chrys in reply toSlowDragon

I have found a 55 min video which will only run for a few seconds. I think I have to join Twitter to view. I don't want to do that thanks, I'm afraid I am a dinosaur and a PC is all I can cope with.

Chrys profile image
Chrys in reply toSlowDragon

Her mother had a goitre, but she has no sign of one.

greygoose profile image
greygoose

15 mcg T3 is only a small dose, so splitting it into 3 might not give her enough to flood the receptors. Has she ever tried taking it all at once? That works better for a lot of people.

Does she take each dose on an empty stomach, without food or drink for an hour and leaving at least two hours before taking any other medication of supplements? That's rather difficult when taking it three times a day.

Chrys profile image
Chrys in reply togreygoose

Thanks GG, we may try the T3 in one dose, post the GP visit tomorrow. Paul Robinson says that it is OK to take T3 with food, but we have always taken it as T4 away from food and other supplements.

greygoose profile image
greygoose in reply toChrys

Yes, I know he does. But, the numbers don't bear that out. We see people on here, taking T3 with food, want their blood test results just don't correspond to the dose they're taking. I know it's a popular idea that T3 doesn't bind, but not all popular ideas are correct.

I always get TSH, free T4 and free T3 done. Some people seem to need in range free T4 while others do fine with it very low. Doing all the tests and keeping a log of how you feel gives you a way to keep track of what suits you. It probably is too low a dose unless she was doing OK on less than 75mcg of levo.

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