Best place to test Ft3 and Rt3

[Charlyemmalouise]

Hello hello

My doctor wants me to test reverse T3 in addition to FT3.

I am struggling to find an online company that does this affordably. Since they lump a bunch of other tests in with them and then charge a few hundred pounds.

I had everything under the sun tested a couple of months ago so now I just really need these two

Anyone have any suggestions? Have looked at Blue Horizon and MediChecks...

Thanks!

[SlowDragon Administrator]

looking at previous posts, you’re on T3 only

There’s no point testing Reverse T3

Very expensive test as blood is sent to USA for processing

Only relevant if on very high dose levothyroxine

[Charlyemmalouise in reply to SlowDragon]

yes I was a bit puzzled also when she suggested rt3 but when I asked her why, she said to check that there is nothing else possibly driving it up..?

[SeasideSusie Remembering]

Charlyemmalouise

Why does your doctor want rT3 tested? It's an expensive test wherever you get it and it takes quite a long time to get the results as the test is done in the US.

Rt3 is a bit of a myth. Testing can tell you if your rT3 is high but it can't tell you why it's high and there are many, many reasons for high rT3 and an excess of unconverted T4 is the one and only reason it can be connected to your thyroid so depending on what your actual FT4 and FT3 results/ranges were at the time that may or may not have been the cause.

However, I understand that reverse T3 doesn't hang around long because it eventually converts to T2, etc, so it's not necessarily a problem. See article by Paul Robinson here:

paulrobinsonthyroid.com/rev...

and there's more in this article here:

thyroidpatients.ca/2019/01/...

If not caused by an excess of unconverted T4, the other conditions that contribute to increased Reverse T3 levels include:

· Chronic fatigue

· Acute illness and injury

· Chronic disease

· Increased cortisol (stress)

· Low cortisol (adrenal fatigue)

· Low iron

· Lyme disease

· Chronic inflammation

Also selenium deficiency, excess physical, mental and environmental stresses. Also Beta-blocker long-term use such as propranolol, metoprolol, etc. Physical injury is a common cause of increased RT3, also illnesses like the flu. Starvation/severe calorie restriction is known to raise RT3. Diabetes when poorly treated is known to increase RT3. Cirrhosis of the liver. Fatty liver disease. Any other liver stress Renal Failure. A fever of unknown cause. Detoxing of high heavy metals.

Other articles

zrtlab.com/blog/archive/rev...

verywellhealth.com/reverse-...

Testing FT3 is easy but it must be done at the same time as TSH and FT4. The cheapest way to do this is with a fingerprick test from an NHS lab in Exeter (Monitor My Health) which offers this to the general public for £26.10 with code here:

thyroiduk.org/help-and-supp...

Medichecks and Blue Horizon both do the basic thyroid panel but are more expensive.

If your doctor wants these tests done, why is he not suggesting where to do them?

I've just seen from a previous post that you were taking T3 only, is this still the case? If so there's no way you have an excess of unconverted T4, you're not taking any T4 and your Free T4 at that time was 3.3 (12-22) so if you did test rT3 you are left with the question what is causing it because it wont be anything to do with your thyroid.

[Charlyemmalouise in reply to SeasideSusie]

yes I was a bit puzzled also when she suggested rt3 but when I asked her why, she said to check that there is nothing else possibly driving it up..?

[SeasideSusie Remembering in reply to Charlyemmalouise]

So she doesn't seem to know that if the result is high the test wont tell her why and that it wont hang around long 🤷‍♀️. Are you paying for this ignorance?