Low T4, Normal T3, on NDT and considering movin... - Thyroid UK

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Low T4, Normal T3, on NDT and considering moving back to Levothyroxine. Advice required please.


Hi ,

I have Hashimoto's and also Chronic Fatigue Syndrome for several years, which I have been managing with various nutritional supplements and NDT.

At the time of taking the bloods below i was on 3 grains of Thiroid NDT (1 grain = 60mg Thyroid)

I've been feeling okay the last couple of years but recently I've been having some symptoms so I had some bloods done.


1. Brain Fog (this had almost disappeared the last two years).

2. Tiredness, fatigue and lethargy.

3. Stiff back, stiff joints and muscles.

4. Disproportionate tiredness and brainfog after excercise.

Bloods (7 march 2019):

TSH = 0.395 mIU/L (Range: 0.27 - 4.2)

FT4 = 9.110 pmol/L (Range: 12 - 22)


FT3 - 4.64 pmol/L (Range: 3.1 - 6.8)

rT3 = 8.0 ng/dL (Range: 10 - 24)

T3/rT3 Ratio =

37.76 Ratio (Range: > 15)

TGab = 800.000 kU/L (Range: < 115)

TPab = 235 kIU/L (Range: < 34)

B12 = 80.100 pmol/L (Range: 37.5 - 188)

D3 = 90.3 nmol/L (Range: 50 - 175)

Ferritin = 115 ug/L (Range: 30 - 400)

Folate: 13.11 ug/L (Range: > 3.89)

C- Reactive Protein =

0.55 mg/L (Range: < 5).

I made an excel chart (see attahment) of all my bloods over the last 4 years and I noted the following:

1. Since June 2017 (when I transitioned from Levothyroxine to NDT, my FT4 drastically reduced but my T3 has been around the same (normal )range before and after starting on NDT .

2. my TGab in June 2017 was only 105 and now its 800.

3. My general thryoid and CFS symptoms have improved since taking NDT - which is strange as the T3 was similar before and after. They suddenly came back in February.


1. Is having low T4 a problem if T3 is Normal? My GP wants me to start taking T4 again with the NDT, which I am thinking is a good idea but need some advice on.

3. My TGab's have shot up - and my throat has been hurting slightly for a couple of months - i'm worried that the antoibodies are really attacking and eating up my thyroid gland. Could this be due to the NDT or could it be just a random flare up? Is there anything I can do to stop the antibodies attacking the thyroid gland? I am already on a Gluten Free Diet.

4. After the bloods test above (and before the results came back) - I immediately went to 4 grains of NDT, and starting taking more Vitamin D (in the past I took Vit D booster as I was deficient and it drastically reduced the Brain Fog). I am feeling much better with my symptoms but am concerned that 4 grains may be too much.

Please can anyone throw some light / advice, the main advice needed is if i should stay on 4 grains of Thyroid or take T4 with a reduced dose of NDT -

Much appreciated and thanks in Advance!


15 Replies

Once you take any T3, as in any NDT, your TSH and FT4 result will go down.; it doesn’t matter if FT4 is low because it is not an active hormone only storage to convert into T3. You say your FT3 at 4.63 is normal, but it isn’t needs to be nearer 6 on that range, and the NDT perhaps has not improved it. I can’t read the scale on your lovely graph...it needs a key. Antibodies are rather random, some try a gluten free diet as you have, but also even try dairy free for 3 months plus, as they can help reduce the antibodies. I have Hashi, hypothyroidism and fibromyalgia and gone done Dr. Lowe’s route ( his papers are archived on Thyroid U.K. website)...he believed fibromyalgia ( not sure about CFS) was due to undertreated hypothyroidism. I could never get my FT3 to anywhere near halfway thru it’s range, till I added T3 to levo. Was at 50 mcg T3 to 100 mcg T4, ie not at same proportion of T3 to T4 found in NDT, so perhaps you need to add T3 to current dosing. Your Vit D, b12, ferritin are low...this might be giving you some symptoms and also compromise thyroid health/ conversion. I’ve never taken NDT, are the results from being on 4 grains? Reverse T3 is rather controversial....it can just indicate there is something ‘off’ but anything from acute or chronic health conditions ( like CFS?), dieting, inflammation, gut infections etc etc.

in reply to Judithdalston

Hi Judithdalston, Thankyou so much for your response - apologies for not responding sooner - i've been finding it difficult to process everyones responses till now due to lack of mental energy in ttrying to figure all this out again!

Can you elaborate on why you think my T3 needs to be around 6? I'm petrified about adding T3 and doing all the research behind it and also i have no idea where to get it!

Do you think a combination of Levo and NDT would be a bad idea? I'm also concerned about my TGab Antibodies - i keep imagining my thyroid is been eaten alive and i wont have one left!

The results were based on 3 grains of NDT. Since then i've been taking 3 grains somes days and 4 days others - in no set pattern. I'me worried i might be taking too much? Aslo, since i've been doing this my tinnitus has gotten worse.

in reply to Ash-S

That’s ok, I can underst and that... but now I have forgotten the thread! I tend to assume hypos have gone onto NDT or T3 because they were not converting T4 to T3 well. But looking above you said you didn’t notice much difference with your FT 3 before or after. To get halfway thru your FT3 range you need a result of 4.95, so might feel better with even higher say 75% thru range which would be 5.875. If you do convert ok then levo. would raise your FT3 but with having the T3 in the NDT your results still would bear no resemblance to the ranges. Perhaps you would be better off just on levo. for a while. Alternating 3 or 4 grains of NDT may ‘confuse’ the body ...you can do this ok with T4 but not T3 due to the different half lives of the two, your body may feel starved of T3 one day, or over medicated the next. Better 3.5 etc every day. Tinnitus worse might indicate hypo, but have you checked your B12 recently - it can produce ear problems. And of course ferritin, folate and vit D? I’ve been surprised how important it is to get vits/ mins optimal ie upper half of range.

You like me have TgAb antibodies, most on forum have high TPO. From what I can gather TgAb don’t quite behave like TPO, yes we are Hashimoto’s and have autoimmune antibodies, but I think I have read gluten free etc doesn’t work as well. I never knew about this diet, and since first year of diagnosis 14 years ago with TgAb at 800, have never had raised TgAb again...no idea if this means a have no thyroid left, or what. You could try gluten free, even dairy free, diet for 2-3 months to see if the TgAb goes down. I’m still trying to get my thyroid health sorted too, just asked Medichecks to send cortisol/ adrenal test...can be reason for our problems. Medichecks have 20% off everything till midnight...you don’t need to use kits immediately.


The following link is from a doctor who only took one initial blood test and thereafter it was all about relief of symptoms.It might be helpful. He would never prescribe levo only NDT or T3 for patients who were resistant to thyroid hormones.


in reply to shaws

Thankyou Shaws


On NDT you ALWAYS need FT3 tested

When was FT3 last tested?

Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and fasting. Last Levothyroxine dose should be 24 hours prior to test, (taking delayed dose immediately after blood draw). This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)

If/when also on T3, or NDT make sure to take last dose 8-12 hours prior to test

Is this how you do your tests?

Have you considered trying increase in dose of NDT

The thyroid pharmacist Isabella Wentz says NDT can cause antibodies to rise for some people with Hashimoto's


The other more flexible dosing option is Levo plus small dose of T3

in reply to SlowDragon

Hi Slowdragon, apologies for the late response and thankyou so much for your advice.

FT3 was tested at the same time as all the other tests (6th March). Yes i do fasting bloods in the morning before i take my NDT meds. I've been taking the blood tests as per your advice.

Should i be worried about my Tgab antobodies? I imagine my thyroid being eaten up alive!

Also the tinnitus has got worse.

I'm thinking if I revert back to Levo with a reduced dose of NDT it might reduce the Tgab antibodies and also reduce the Tinnitus?

Is there any harm (or any point ) doing this?

Or should I consider taking Levo with T3 as JudithDalston is suggesting - i'm just daunted by the idea of finding T3 supplier as i understand i'll have to get it privately from germany and I have no idea how to go about doing this.

in reply to Ash-S

Message me if you want to go down cheaper T3 route without prescription.

in reply to Judithdalston

Thanks Judith, I'm trying to figure out how to private message you!

in reply to Ash-S

Roughly where in the Uk are you?

Changing from NDT to Levo plus T3 may not lower TG antibodies any more than NDT.

I am on Levothyroxine plus T3. Have had Hashimoto's and been on Levothyroxine for over 26 years. Been on Levothyroxine plus T3 for almost 3 years. TSH suppressed. Strictly gluten free diet and all vitamins optimal. My TG antibodies are still way over range. TPO antibodies are slowly dropping, since going gluten free 4 years ago, but still over range. I get my T3 on NHS prescription

I do find I need good levels of FT4 to prevent low B12 symptoms.

One option for T3 is to see a thyroid specialist for private prescription for T3 initially. Then push to get treatment on NHS

Email Dionne at Thyroid Uk for list of recommended thyroid specialists

please email Dionne at


in reply to SlowDragon

Thanks slowdragon! I am in East London.

Just to clarify - are you suggesting Levo +T3?

What do you think about adding T3 to my current 3 grains of NDT?

Thanks in advance.

in reply to Ash-S

Personally I didn't get on with NDT, So I don't have experience of adding T3 to NDT

According to Isabella Wentz the Thyroid pharmacist, page here....some Hashimoto's patients see antibodies rise on NDT


But if you feel better, perhaps just trying slightly higher dose

Your B12 and folate could be higher, as well as vitamin D


Supplementing a good quality daily vitamin B complex, one with folate in not folic acid may be beneficial.


B vitamins best taken in the morning after breakfast

Recommended brands on here are Igennus Super B complex. (Often only need one tablet per day, not two. Certainly only start with one tablet per day after breakfast. Retesting levels in 6-8 weeks ).

Or Jarrow B-right is popular choice, but is large capsule

If you are taking vitamin B complex, or any supplements containing biotin, remember to stop these 7 days before any blood tests, as biotin can falsely affect test results



Thanks all for your responses, and apologies for not thanking you sooner - i have responded to you each individually to cover all the points. I'm a bit daunted about what i should do next regarding changing the meds to T3 or reverting back to Levo and NDT combo.

Tinnitus worse since increasing NDT (but could this be a coincidens and not related to thyroid?)

Any more advice would be greatly appreciated. Thanks in advance You are all angels!

in reply to Ash-S

HealthUnlocked Help facility has these two topics:

How do I send / report / delete private messages?


How do I view private messages?


in reply to helvella

Thankyou Helvella!

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