Testing of reverse T3.

[Rock_chick1]

Could someone tell me the importance of testing reverse T3 please. I've never had it rested and wonder if it would be a good idea, if so, where can I get a test in the UK. I suffer from Hashimotos and on Liothyronine and Levothyroxine which so far haven't helped

[SeasideSusie Remembering]

Save your time and money, the rT3 test is pretty useless, it can tell you if your rT3 is high but it can't tell you why it's high. It's expensive and takes about 3 weeks to get the results as it's sent to the US for testing.

High rT3 can be caused by many things, only one of which has anything to do with the thyroid and that's when there is an excess of unconverted T4 and you will know this from the FT4 and FT3 results, you don't need a rT3 test to show this.

High rT3 could be caused by low ferritin, by an infection, by low-calorie diets, selenium or zinc deficiency, cortisol issues, stress, dieting, chronic illness, inadequate or low iron, chronic inflammation, high cortisol, or liver issues and any other chronic health issues, and probably several more things.

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.

Articles

thyroidpatients.ca/2019/01/...

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

verywellhealth.com/reverse-...

[Rock_chick1 in reply to SeasideSusie]

Thank you for this very helpful info. So basically would one expect a high level of FT4 if they had high reverse T3? I certainly don't have that. Its just that no one can understand why I'm not feeling any improvement from the thyroid meds. If its simply still that I need to tweak the doses or that there is something other than Hashies that hasnt yet been diagnosed

[SeasideSusie Remembering in reply to Rock_chick1]

So basically would one expect a high level of FT4 if they had high reverse T3?

Only if high reverse T3 was due to unconverted excess T4.

If high reverse T3 was due to one of the myriad other conditions then you wouldn't expect high FT4.

If its simply still that I need to tweak the doses or that there is something other than Hashies that hasnt yet been diagnosed

Looking at your results from 15/11/21 what you posted a couple of weeks ago :

TSH : 0.02 (0.27-4.20)

FT4 : 9.9 (12-22)

FT3 : 5.6 (3.1-6.8)

I suggested that your FT4 maybe too low for you and to increase Levo and gradually tweak doses to find your sweet spot.

[Rock_chick1 in reply to SeasideSusie]

SeasideSusie, I have increased the dose of levo as you suggested thank you. The reason I am asking about the reverse T3 is because someone on a Facebook page had said it was a necessary test so I decided to ask on here

[radd in reply to Rock_chick1]

Rock_chick1,

No, not if the enzyme (D3) that converts thyroid hormone to RT3 was so over-active it caused T4 levels to drop.

I personally think knowing RT3 levels is useful sometimes but it's getting them interpreted that's the issue. It is now known that RT3 is inert, doesn’t block T3 receptors or offer clues as to its cause or directly cause hypo symptoms but it is the result of overactivity of that enzyme that is responsible for a large part of hypo symptoms.

Therefore, RT3 can be a good indicator of why meds aren't working in the sense that the cause of underlying symptoms may not be a problem with the meds or dose (unless under/overmedicated).

For instance in cases where there is no reduction in hypo symptoms regardless of dose change it can encourage other causations to be considered as opposed to continuous useless dose titivations. Also in cases of adequate thyroid hormones elevated RT3 would indicate towards not increasing thyroid hormone levels which risk raising RT3 levels further until the cause of the enzyme overactivity was addressed.

Common reasons for elevated RT3 on this forum is autoimmune inflammation, hence the advocation of modulating a highly responsive immune system towards reducing elevated thyroid antibodies because in people with multiple health conditions it can be the tipping point. Also inadequate iron or cortisol levels which then becomes a whole lot more complicated.

However, elevated RT3 can also be the result of basically anything ‘unhealthy’ if done long enough to a degree more than your body can healthily tolerate, ie crash dieting or excessively sedentary lifestyle with a processed/sugar laden diet. Or just life issues such as excess oestrogen that clogs the liver making all detoxification slow and inefficient.

[greygoose]

Its just that no one can understand why I'm not feeling any improvement from the thyroid meds. If its simply still that I need to tweak the doses or that there is something other than Hashies that hasnt yet been diagnosed

Well, high rT3 itself wouldn't have anything to do with your lack of improvement. However, low FT3 would. If you're a poor converter, you rT3 would be high - assuming that your FT4 is high - and your FT3 would be low. Have you had your FT3 tested?

[Rock_chick1]

Grey goose, I see. And yes here are the results. Just a basic panel to check levels this time. Ft3 was too high before. After reducing Lio dose it is now a little low

Photo of test results

[SlowDragon Administrator]

Many people on levothyroxine plus T3 combination find they need Ft4 and Ft3 roughly at least 50% through range

Obviously your most recent results show very low Ft4

Have you increased your levothyroxine dose?

[Rock_chick1 in reply to SlowDragon]

Thanks Slowdragon. Since these test results I have upped it by 25mcg so now on 75

[SlowDragon Administrator]

How much levothyroxine were you taking BEFORE adding T3?

[Rock_chick1]

Slowdragon, it's a bit of a funny one as I did just the opposite. Basically I was left untreated for a long time as all my gp offered me was levothyroxine and I couldn't tolerate even the smallest of doses. However a few years on I had a private practitioner who, being aware of this, tried me on Liothyronine. I titrated up on doses slowly until I got to 35 but didnt feel better at any stage. I then started adding levo, again very gradually and this time I round I could tolerate it. So the upshot of it all is that I was on 50 levo and 20 Lio when this test was taken. As I said in my last reply I have just increased the Levo to 75