T3 Supplementation Advice Please.: Hi all, I hope... - Thyroid UK

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T3 Supplementation Advice Please.


Hi all,

I hope that you Thyroid experts can help, as you all did for me recently :)

My partner has had a few thyroid function blood tests done recently, as Hypothyroidism was suspected (She has already been diagnosed as suffering from Fibromyalgia for the last few years). There is a history of Hypothyroidism in her family history. The results are below, and her doctor says these are fine as within range so no supplementation is required:

T4: 15 pmol/L - (Range 11-25)

TSH: 2.19 mU/L - (Range 0.27-4.20)

TPO : Negative

However, as we all know from experience that to feel really good T4 should be in upper range, and TSH should probably be in the lower range.

She had an operation on her neck/spine 18 months ago and her TSH has always been varied (mostly too high) since then: 7.94, 5.26, 0.83, although it has dropped back into range now oddly. T4 has always been in lower range also: 11.1, 13.2, 12.6.

We are considering extra self-supplementation with T3 to optimise her Thyroid levels in a hope that this may make her feel better. No point in asking the doctor to do this obviously as as long as tests are in range they are happy :(

We have obtained Tiromel 25mcg, and think that one of these a day would equal 75mcg Levothyroxine. We are hoping to try one a day for a few weeks to see if this helps at all, and maybe even help with the Fibromyalgia also.

Anyone had experience of this, and is this dose ok?

Many thanks :)

13 Replies

Do you have any t3 test results? I guess the lab wouldn't do them w tsh in range?

I'd start quite low, like w 10, and give it a few weeks. These tablets are equivalent to 75-125 levo depending on what you believe (differing opinions). Just fyi when the next blood test is due you may find the t3 is higher in range but t4 is lower. If you're taking t3 that's normal; t4 high in range is only the desired effect when on levo alone.

Have you thought about ndt? Also avail otc (online anyway), and it would give her a little t4 in reserve.

What are her other symptoms apart from the fibromyalgia? and did they not test the t3 level?

DavyB in reply to rozdee

They don't routinely check T3 it seems :(

Fibromyalgia has very similar symptoms to Hypothyroid: fatigue, brain-fog, aching muscles, stiff joints, depression, brittle nails/hair, so difficult to distinguish between most of them it seems :(


Fluctuating thyroid levels can be caused by autoimmune thyroid disease (Hashimoto's) which causes 90% of hypothyroidism. thyroiduk.org.uk/tuk/about_...

I would order a home finger prick test from Blue Horizon or Genova to check FT3 level and antibodies before taking T3. FT3 should remain within range.

If your partner decides to self medicate anyway, she should buy a pillcutter and quarter the 25mcg tablet starting with 6.25mcg to see how she tolerates T3 and increase in 6.25mcg increments every couple of weeks.


I am not a medical professional and this information is not intended to be a substitute for medical guidance from your own doctor. Please check with your personal physician before applying any of these suggestions.

DavyB in reply to Clutter

Thanks for the reply and advice. The antibodies test (TPO) was negative in her recent tests so i guess we can rule out Hashimotos.

Clutter in reply to DavyB


Not conclusively. Many patients are negative for TPOab but positive for thyroglobulin antibodies (TgAb). It's unlikely your partner's GP will be able to order TgAb but it is available via Blue Horizon and Genova.

DavyB in reply to Clutter

Thank you, will check out the cost of that :)

I would not start with a full tablet (25mcg) dose. Given you are stuck with 25s, I would quarter them (is that possible?) and start with a 6.25mcg dose. Try that for a few days. Keep in mind that T3 will cause her TSH to plunge, reducing her natural thyroid output, so you will likely have to quickly increase T3. You did not explicitly state if she is on T4, or if so, what dose of T4 she is on now; is it 75mcg? If so, it is probably not a good idea to drop the T3:T4 ratio below 1:4. (For instance, I am on T3+T4=15+75, which is a 1:5 ratio.) That is, if she is on 75mcg T4, then you probably should cap daily T3 at three-quarters of 75, i.e. at 18.75mcg.

To avoid going hyper, you could use Abbott's figure for T4-only full replacement of 1.7mcg/kg body weight. Once you know the T4 full replacement based on body weight, you can use the fact that each mcg of T3 is equivalent to 3-4 mcg of T4, to reduce T4 dose as you add T3.

On the other hand, if she is not currently on T4 at all and you are proposing to put her on T3-only: then the best approach initially is to split the T3 dose into multiple doses over the day. For instance, while I was on T3-only, I took five 12.5mcg doses over the course of a day; that worked out to about 0.82mcg/kg body weight. There are some people who can tolerate a large dose of T3 once per day, but I would not recommend that to start.

Hi, she is not on any medication for thyroid as test results are within range (according to Doctor) However, a lot of fibro sufferers swear by the benefits of taking T3 to alleviate symptoms.

Eddie83 in reply to DavyB

Definitely. The late John C. Lowe put out a study on his observation that T3 is the single most needed substance needed to alleviate fibro.

DavyB in reply to Eddie83

Thats comforting to know, thank you :D

Has your partner had a vit D test? I suffered with fibromyalgia for years before I found out I did not have it. 80% of people diagnosed with fibromyalgia are actually vit D deficient. Well worth a blood test if not already tested.

DavyB in reply to dizzy864

Yes we checked that recently, and indeed she was low on Vit D. We pumped that up already, but thanks for the reply :)

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