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Help needed with blood results - ferritin and ft3 dropping

Hi, I am a 47 year old male, diagnosed with hashimotos hypothyroidism and secondary hypogonadism (pituitary related) late 2016.

Despite both being treated I continue to feel very ill.

Endo has not seen latest results yet so I want to understand why my FT3 and TSH have dropped despite no change to the dose, and why Ferritin has gone down so much, so I can ask the right questions on the day.

Blood tests over that period are as follows:

Before diagnosis:

TSH 5.8 0.50 - 5.00 mIU/L

TPO Antibody 304 0.00 - 6.00

December 2016 - 75mcg Levothyroxine:

TSH 3.37 0.27 - 4.20 mIU/L

Free T4 16.37 12 - 22 pmol/L

Free T3 4.26 3.1 - 6.8 pmol/L

TPO Antibody 372.5 0.00 - 6.00

Ferritin 524.8 30 - 400 ug/L

March 2017 - 125mcg Levothyroxine:

TSH 1.32 0.27 - 4.20 mIU/L

Free T4 17.2 12 - 22 pmol/L

Free T3 5.25 3.1 - 6.8 pmol/L

Ferritin 490 30 - 400 ug/L

May 2017 - 150mcg Levothyroxine

TSH 1.18 0.27 - 4.20 mIU/L

Free T4 14.8 12 - 22 pmol/L

Free T3 4.82 3.1 - 6.8 pmol/L

Ferritin 185 30 - 400 ug/L

August 2017 - 175mcg Levothyroxine

TSH 0.849 0.27 - 4.20 mIU/L

Free T4 16.9 12 - 22 pmol/L

Free T3 5.7 3.1 - 6.8 pmol/L

Ferritin 215 30 - 400 ug/L

November 2017 - 200mcg Levothyroxine

TSH 0.148 0.27 - 4.20 mIU/L

Free T4 19.4 12 - 22 pmol/L

Free T3 6.38 3.1 - 6.8 pmol/L

Ferritin 153 30 - 400 ug/L

February 2018 - 200mcg Levothyroxine

TSH 0.05 0.27 - 4.20 mIU/L

Free T4 19.2 12 - 22 pmol/L

Free T3 5.73 3.1 - 6.8 pmol/L

Ferritin 67.3 30 - 400 ug/L

Total vitamin D 109.4 >49.90

The following are also high above normal range:

Cholesterol and triglycerides


Creatine kinase

17 Replies

Your a pretty good converter of FT4 to FT3. Very impressive

However in last result FT3 has dropped, possibly because TSH is now virtually suppressed

This may explain ferritin dropping

You might now need small dose of T3 adding or yet more Levo added

Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,

"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.

In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l.

Most patients will feel well in that circumstance. But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.

This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."

You can obtain a copy of the articles from Thyroid UK email print it and highlight question 6 to show your doctor

 please email Dionne at


Professor Toft recent article saying, T3 may be necessary for many or we have to have high FT4 and suppressed TSH in order to keep FT3 high enough


Your high thyroid antibodies show you have Hashimoto's

Do you supplement vitamin D? It's a good result

What about B12 and folate? Had these tested?

Hashimoto's affects the gut and leads to low stomach acid and then low vitamin levels

Low vitamin levels affect Thyroid hormone working

Poor gut function can lead leaky gut (literally holes in gut wall) this can cause food intolerances. Most common by far is gluten

According to Izabella Wentz the Thyroid Pharmacist approx 5% with Hashimoto's are coeliac, but over 80% find gluten free diet helps significantly. Either due to direct gluten intolerance (no test available) or due to leaky gut and gluten causing molecular mimicry (see Amy Myers link)

You don't need any gut symptoms

But don't be surprised that GP or endo never mention gut, gluten or low vitamins. Hashimoto's gut and gluten is very poorly understood

Changing to a strictly gluten free diet may help reduce symptoms, help gut heal and slowly lower TPO antibodies

Ideally ask GP or endo for coeliac blood test first









Hi SlowDragon,

Thanks for your reply.

As Ferritin level has dropped pretty steadily from 524 to 67.3 would this actually be linked to suppression of TSH? Also as the latest fall is from 153 to 67.3 and TSH has only gone down a small amount (0.148 to 0.05) it seems that small change has had a big impact on Ferritin levels which doesn’t correlate with previous drops?

Is it typical for FT3 levels to fluctuate when on the same dose of Levo? and rather than increasing the amount of T4 in my blood would adding T3 be preferable or is it much of a muchness seeing as I have no conversion problems?

I supplement with a daily dose of 7500iu Vitamin D as my level was in the mid teens around 2 years ago and that dose seems to keep me hovering around 100.

Serum B12 1210 187.00 – 883.00ng/L

Serum folate 15.3 3.10 – 20.50 ug/L

Interesting article by Professor Toft and not one I had managed to find myself - will have to print off and show / educate my GP.



TSH has dropped because it's taken time for 200mcg to build up T4 and T3 to levels that your pituitary recognises as satisfactory so TSH can be reduced. FT4 and FT3 have dropped a little without the higher TSH stimulation.

There's no association with TSH and ferritin.

Ferritin is stored iron. Levels fluctuate throughout the day as the body draws on iron from ferritin and dumps excess iron back into ferritin. Withdrawing iron into ferritin can starve bacteria. High ferritin (assuming you have not supplemented too much iron) is a sign of inflammation or infection in the body. Dropping from 524 to 153 indicates the inflammation or infection resolved. Ferritin is optimal halfway through range which in general is >75. Low ferritin can indicate iron deficiency anaemia. If ferritin becomes very low you should ask your GP to do an iron panel and full blood count to rule out deficiency.

FT3 level fluctuate according to circadian rhythms and generally lag about 90 minutes behind TSH levels. See the graph in healthunlocked.com/thyroidu... FT3 was in the upper third of range generally thought to be optimal so your conversion is very good and you don't need to add T3 to Levothyroxine.

VitD 100 is optimal. Some people do need a high dose of D3 to maintain vitD levels. Do make sure to have annual or biannual vitD tests as toxicity can lead to development of kidney, bladder and gallstones.

High B12 can indicate underlying illness so if you are not supplementing B12 you should see your GP.

Folate is optimal.


Hi Clutter,

Thanks for the reply.

I have never supplemented iron so it must have been inflammation that caused the high numbers. That being the case I guess the next time I have it tested it should not have gone down at all seeing as it is now at a 'normal' level?

If ft3 is where it needs to be does that mean there’s no need for a dose increase regardless of continuing symptoms?

Supplementing B12 which accounts for high level.



Ferritin 67 is low normal. It is optimal >100 for men through to halfway through range so if ferritin drops very low in range you may need to check that you've not become iron deficient.

There is scope to increse dose to raise FT4 and FT3 higher in range to see whether symptoms improve but TSH 0.05 is already suppressed so I think your GP will be reluctant to increase dose. Read Treatment Options in thyroiduk.org.uk/tuk/about_... Email dionne.fulcher@thyroiduk.org if you would like a copy of the Pulse article to show your GP.

GPs have been told to get a NHS endo to recommend T3 before they prescribe it. It is very difficult for new patients to get it prescribed. If you want it your best bet is to buy online and self medicate.

I'm going to delete the duplicate post you wrote yesterday as you have replies on this thread.


Hi Clutter,

Please excuse my lack of knowledge but would there be any other reason for ferritin levels to fall? And regarding high ferritin, Would this account for my sweat smelling of metal?

As symptoms aren’t improving - particularly head pressure, aching joints and muscles and restless sleep - and the GP feels the dose is as high as it can go is there also a chance they may withdraw treatment altogether and say it isn’t working? I’m just conscious of the fact that levo was started on a ‘trial’ basis as my TSH was less than 10.



Apart from ferritin dropping when infection/inflammation improves the only other reason I can think for ferritin to drop is when someone is losing iron.

Levothyroxine dose can go higher even if your GP isn't comfortable increasing dose. Treatment is given according to blood levels so Levothyroxine is working even though it may not be relieving your symptoms adequately.

NICE CKS recommends:

Advice should be sought from an endocrinologist (or referral arranged) if the person:

Has adverse effects from treatment with LT4.

Has cardiac disease.

Has an abnormal thyroid gland structure, atypical thyroid function tests, or an unusual cause of hypothyroidism (for example due to drugs such as amiodarone).

Has persistent symptoms despite treatment with LT4.



Hi Clutter,

If it was as easy to get a prescription for T3 as it is to get T4 would you suggest the addition of T3 rather than a higher dose of T4?

And if symptoms persist despite treatment with T4 what is the ‘normal' course of action or are there options?



I don't think a higher dose of T4 will be helpful as TSH is suppressed and FT4 high in range. FT3 is 5.73 which is high in range. It's low FT3 which causes hypothyroid symptoms so I doubt you'll benefit from adding T3.

There are few GPs or endocrinologists who will accept that patients are allergic to, or having adverse reactions to, Levothyroxine. If you've tried several different brands without improvement the 'normal' course of action for patients with persistant symptoms when they are optimally dosed and vitamin and mineral deficiencies are ruled out is to tell the patient their symptoms are in their head and to offer them antidepressants.

For people not doing well on synthetic Levothyroxine natural dessicated thyroid (NDT) which is combination T4+T3 treatment can be beneficial. It isn't licenced for UK use so most members using NDT have private prescriptions or buy online and self medicate. You may need to try more than one brand to find the one which suits.

If, after being optimally dosed a few months on NDT, symptoms persist, it may be worth trying T3 only in case you have an intolerance to T4 in Levothyroxine and NDT.


Hi Clutter,

From what I have read on other posts the optimal level of FT3 is top quarter within range (ie above 5.88) and 5.73 is short of that. So surely there's room for increase there, even if FT4 goes above range?

And not quite sure what you mean by 'it's low FT3 which causes hypothyroid symptoms' as wouldn't that mean anyone with FT3 above say half way in range should not have symptoms related to hypothyroid? If that is the case then I am totally confused as have read a number of posts about people not feeling well until the magic moment FT3 was within the upper quarter or TSH was fully suppressed or FT4 was slightly above range?



Low FT3 is usually <4.0 in your range. Optimal is in the top third of range ie 5.5 - 6.8. There is scope for an increase as long as FT3 remains <6.8. I simply doubt you will find adding T4 or T3 when FT3 is already good beneficial but by all means try it to see.


Majority of us with Hashimoto's possibly have low stomach acid if not also taking small dose of T3. It's often the prime result when T3 is stopped, vitamin levels crash out. The gut needs high acidity to cleave vitamins from food.

20% of conversion of T4 to T3 happens in the gut

Brilliant film


If gut biome is affected by the Hashimoto's (as indicated by falling vitamins) then it's likely we have low stomach acid, leaky gut and gluten issues as well as impaired conversion of T4 to T3

Suggest you try strictly gluten free diet. You might be astonished at results

Also possibly consider a T3 friendly endo and perhaps trying a slightly reduced dose of Levo with small dose of T3

To keep ferritin up, try liver once a week

On plus side your ferritin was very high before (too high) due in all likelihood to Hashimoto's

1 like

Do you take a good quality vitamin c? This helps to improve ferritin level and is very good for our health.

Personally I don’t feel well unless my free t4 is at the top or just above


Hi Chippysue,

I take a good quality multi vitamin which has 250mg of vitamin c. Is this enough?


I would want more than that. Many nutritionists say 2 x1000 or even 3.

When I feel under the weather I have lots up to bowel tolerance every few hours.


I know this is old post

Are you still taking multivitamin? Not recommended on here, especially with Hashimoto's

These often have iodine in and definitely not good idea with Hashimoto's



Have you tried strictly gluten free diet


Hi Chippysue,

Which is the best form to take and is there a supplement you would recommend?

Also, is your TSH suppressed with a high ft4?


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