reverse T3 testing

[Sofie007]

My results last month showed poor conversion from T4 to T3. I am on levothyroxine 75 and added extra iron , D3 and K2 since a month. I was feeling much better but since a week i feel lethargic again. I am wondering if I should test for reverse T3 before starting with T3 hormone. Any advice is very welcome.

[greygoose]

Waste of time and money. It won't give you any information that you can't get from TSH/FT4/FT3. It will tell you if your rT3 is high, but it won't tell you why - and there are many, many reasons for high rT3, and only one of them has anything to do with thyroid. So, I wouldn't bother, if I were you.

[Sofie007 in reply to greygoose]

Hi Greygoose, thanks for the fast reply 😊! Isn’t it important to “flush out” the reverse T3 by for example lowering your T4 for a few days? I thought i read it somewhere. If RT3 is high, you will feel tired no matter what you do, or is that not the case? Thanks a lot 🙏🏻

[greygoose in reply to Sofie007]

Yes, well, people write a lot of rubbish about rT3. It 'flushes' itself out because it only stays in the system for about two hours before it is converted into T2. And, it's inert so it doesn't make you tired or anything else.

Obviously, if you stop/lower T4, the rT3 will also reduce, but as soon as you go back to your normal dose, the rT3 will rise again if you haven't eliminated the root cause. But, it doesn't always mean that your FT4 is too high. There could be all sorts of other things causing it, like a virus, or a low-calorie diet.

So, no, it's not only not important, it's not even possible to just get rid of it like that. And it's certainly not necessary.

[jimh111]

Very expensive test, not very reliable and no use. bebe Save we your money and time.

[Sofie007 in reply to jimh111]

oh ok, i had no idea it was expensive. It shouldn’t be. Thanks!

[jrbarnes]

I agree with what you were told in your first post about the iron. The point is to get the most T4/T3 conversion but in order to do that you need to make sure that if all your iron levels are low that you bring them up. Low thyroid and low iron can lead to lack of appetite which makes the problems worse. In my case the low iron/thyroid caused me to eat less and with several hours between meals. When you don't feel well you don't want to eat as much or lack the energy to prepare proper meals. This led to even less conversion. You can continue to increase the Levothyroxine but it won't help until you correct any vitamin mineral nutrient deficiency. I also had higher FT4 and bottom of range FT3. The dosage guidelines state 1.6 mcg per kg of body weight plus and factor in that you will not absorb 100% of the Levothyroxine in tablet form. Currently I weigh 59 kg and take 112mcg of Levothyroxine and 10 mcg of T3. I did not add the T3 again until I increased my calories to get enough carbohydrates(no fasting) and started Thorne iron at 100mg every other day for 4 weeks then retest. From the low iron I was losing hair and experienced terrible dizziness and weakness, which has now subsided. Doing these two things have significantly improved my conversion so that I was able to add T3 and then raise my Levothyroxne.