Thyroid UK
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T3 lower, TSH much higher after T3/T4 time-release - take T3 only, or T3 with levo?

Hi all, I'm from the U.S. but find info here great so wonder if you could advise what I should do next.

Main question is, should I take T3 (5 mcg.) only to flush out RT3?

Or take the T3 in addition to my old T4 levothyroxine, and if so, 75 mcg. of the T4 or just take 37.5 mcg (1/2 tab)? This was first time ever adding in T3 but appears the time-release was not getting absorbed since my T3 level actually went lower & TSH went up - do you agree?; and I'm not converting well.

After below results, dr. just doubled the dose to T3 25/T4 110 (I wanted just T3 or less T4, but he said you "have to" have T4..). Felt worse on that so stopped it. Saw a different doc who prescribed T3 but I do wish it was 10 mcg. I have no heart/jittery issues with the T3, feel good.


Jan. 5, 2018 [after 6 weeks on T3 12 mcg./T4 50 mcg. time-release]

FT3 - 2.32 L (2.5 - 4.30 pg/mL)

he said not necessary to test RT3 again...

FT4 - 1.0 (0.8 - 1.8 ng/dL)

TSH - 11.74 H (0.27 - 3.50 mIU/L) (super high for me!)

Sept. 11, 2017 - these labs were based on 75 mcg. levothyroxine

FT3 - 2.41 L (2.5 - 4.30 pg/mL)

RT3 - 20.41 (9.0 - 27.0 ng/dL )

FT4 - 1.1 (0.6 - 1.4 ng/dL) [Aug. 9, 2017 (different lab)]

TSH - 2.39 (0.34 - 5.60 mIU/L) [Aug. 9, 2017 (different lab)]

TgAB - 1.76 H (0 - 0.5)

TPO - 12.14 (0-100)

Ferritin 40 ng/mL (13-150) (blood irons were good tho - not getting to tissues?)

B12 - > 2000 pg/mL (243-894) H

RBC Folate - 1,018 (> 366 ng.mL) H

Vit. D - 55.7 (30-100 ng/mL) (Aug. 9)

Background is I went hypo about a year after menopause. Have been on 75 mcg. levothyroxine since (2005). Didn't totally resolve all symptoms (constipation, dry skin, hair, eyes, tight finger tendons, didn't lose weight easily) but like many of us, I just dealt with it. I don't feel fatigued or cold.

Last April they removed 3 supposedly overactive parathyroid glands, felt great after the surgery (I now believe it was the massive amounts of calcium they had me take), but downhill since. July was super bad, I was losing muscle but started gaining weight which is unusual in summer, could not pee (muscle?), brain fog in afternoon. I had stopped the B12 shots before the surgery thinking I wouldn't need them anymore, but finally got one in July and peed 17 times that day. I believe they were helping my thryoid - they also contain methionone, choline, inositol. anyway, something happened over the summer, not sure what. I've recovered muscle but the weight gain is a big difference.

I don't seem to absorb nutrients? - is this why my blood levels are so high? I have upped my digestive enzymes & betaine, take all the co-factors, zinc, selenium, D. don't eat gluten, eat mostly whole foods although very little!

My D level doesn't seem to go up much either even though in the summer I am in the sun 6+ hours a day and never put sunscreen on my legs. Or some kind of nutrient carrier problem?

The new dr. wants to find out the reason I'm not converting before giving me more T3. Wants to do a hair mineral test, but I don't have enough hair yet!

I do wonder if there is something wrong with my liver.

Anybody has a source of T3 in the U.S. without prescription, let me know.

I'm getting closer to help, just want to move things along. It's like an endless cycle - thyroid levels not optimal so other things in body not working and thus thyroid levels get worse etc.

Thanks for listening and any other advice.

2 Replies

You cannot 'flush out' RT3 as I have read that T4 converts to RT3 and then to T3. There have been misconceptions re RT3:. Excerpt:

Another enzyme called 5-deiodinase continually converts some T4 to reverse-T3. Reverse-T3 does not stimulate metabolism. It is produced as a way to help clear some T4 from the body.

Under normal conditions, cells continually convert about 40% of T4 to T3. They convert about 60% of T4 to reverse-T3. Hour-by-hour, conversion of T4 continues with slight shifts in the percentage of T4 converted to T3 and reverse-T3. Under normal conditions, the body eliminates reverse-T3 rapidly. Other enzymes quickly convert reverse-T3 to T2 and T2 to T1, and the body eliminates these molecules within roughly 24-hours. (The process of deiodination in the body is a bit more complicated than I can explain in this short summary.) The point is that the process of deiodination is dynamic and constantly changing, depending on the body's needs.

The aim of taking thyroid hormone replacements is to get the TSH to around 1 or lower with FT4 and FT3 in the upper part of the range.

I think your TSH is too high and FT3 and FT4 too low so you need either a higher dose of levo to bring TSH down, or some T3 added to T4. Quite a number of researchers have proven that many need a combination of T4/T3 to recover their health and be symptom-free. Other memberswill respond re your vitamins/minerals. Everything has to be optimal.

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T4 converts to T3 and rT3. There was no problem with your rT3 on 75mcg T4 as 20.41 is comfortably within range and isn't high. Your FT3 was below range though so you were undermedicated on 75mcg T4.

Jan 5th you were undermedicated on 50mcg T4 and 12mcg T3 to have TSH 11.74, FT4 low in range and FT3 below range. I think the doctor who prescribed 110mcg T4 and 25mcg T3 was on the right track. I'm not sure how much T3 you are now prescribed but if it is only 5mcg or 10mcg you will be very undermedicated.

TgAb (thyroglobulin antibodies) are positive for autoimmune thyroid disease (Hashimoto's). There is no cure for Hashimoto's which causes 90% of hypothyroidism. Levothyroxine treatment is for the low thyroid levels it causes. Many people have found that 100% gluten-free diet is helpful in reducing Hashi flares, symptoms and eventually antibodies.

Ferritin is stored iron and is optimal halfway through range. You can supplement iron to raise ferritin. Taking 1,000mg vitamin C with iron will aid absorption and minimise constipation.

If you are having B12 injections that will be why B12 is high.

Are you also supplementing folic acid or methylfolate?

VitD is optimal around 50 ng/ml so yours is fine at 55.7.

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