Thyroid UK
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T3 dose

Interested to know the highest dose of T3 anyone has been prescribed by an Endo - without too much begging. My first & previous post was asking if folk thought I stood a chance of successfully suing the NHS for my 30+ years of hell & not being correctly medicated. All endos and docs seemed to want to keep me on the absolute minimum dose of T3. I'm new to this site & it's such a relief I'm not alone.

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Marigold, 60mcg T3 was the dose I was prescribed post thyroidectomy prior to RAI. I'm now on 100mcg T4 + 40mcg T3 combination. 40mcg T3 isn't considered a small dose, it is roughly equivalent to 120mcg Levothyroxine (T4). That doesn't mean that it is sufficient for your needs, of course. Post your recent thyroid results with the lab ref ranges (the figures in brackets after your results) and members will advise whether you are optimally medicated.

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Clutter, I hope you don't mind my asking, but what is your fT3 on this dose?


I won't know until next bloods in September, Gabkad. April 100mcg + 20mcg FT3 was 5.2 (3.2-6.2),FT4 18.4 (9-19).


Clutter, I guess we absorb this stuff differently. I'd need about 150 mcg T4 to get such a high fT4 reading. Do you think you convert at all much? Maybe that's really sluggish. Maybe you are peeing out most of your T4 although, as you've mentioned in the past, you feel better with this amount of T4.

Were you +24 when you got the fT3 at 5.2? Too bad the NHS won't pay for a dose response curve. And it's not there's a device like a glucometer for measuring fT3.

Back to you whenever I get my results from sampling on friday.............. Makes me wonder 100 mcg T4 plus 12.5 mcg T3 with 6.25 mcg T3 +9.5hrs.

I know my 'body' generally does better with high fT4. The brain needs the T3 though.

What I have noticed is with current dose my face is not flushed. People used to ask me all the time "have you been out in the sun?" Yeah right, if only I had the energy for all the sun and fun. Not. Today I skipped breakfast because I had to meet a friend and we only had tea.......but by 1:30 p.m. I was quite pale. And hungry. Ate a 'normal' sized amount of food for lunch and then ate the same again 3 hours satisfied. Hoping to not eat more than a snack in the evening. Too much appetite with this current T3 dosing. And I truly doubt the metabolism has ramped up enough to burn through the calories.


Gabkad, T3 hasn't increased my appetite but it's stopped me losing weight.

I think the over replacement messed me up and I don't think I had a conversion problem. FT4 and FT3 were high for over 7 months but when they looked good on 125mcg I still felt like hell. Felt desperate when FT3 was low and didn't feel better until I stopped T4 for 8 weeks and T3 for 4 weeks before reintroducing T4 plus T3.

200mcg TSH 0.5 FT4 35 FT3 5.8

175mcg TSH<0.01 FT4 30 FT3 7.15

150mcg TSH 0.01 FT4 32.4 FT3 6.58

125mcg TSH 0.01 FT4 16.1 FT3 5.0

100mcg TSH 0.03 FT4 17.1 FT3 3.10

75+20 T3 TSH 0.13 FT4 18.3

100+20 T3 TSH<0.01 FT4 18.4 FT3 5.2


Is it possible this stuff just floats around in the blood and doesn't get into tissues?

I'm truly wondering.

When I was on 150 mcg I don't have my breakdown tests because the doctor died. I don't think after so many years I can get the results. He did tests several times over a three year period and when the goitre finally disappeared, everything was cool. I was feeling awesome.

Everyone else likes to screw around with dosages and I'm not having it anymore.

On 125 mcg I can see why you weren't feeling great. And on 100 mcg even worse.

Yet you do seem to be absorbing well. I would say that you were not converting well though. And making tons of rT3 at the 200 mcg dose.

Well, let's see how the blood profile is like on your current dose.

Are you going +24 with the T3?

Like I wrote before, it's too bad the NHS won't agree with your having the fT3 done at +4, +8, +12 etc. because that would be a huge educational experience.

Do you think now that you are chronic on your T3 meds, the actual swings up and down are not as wild?

(I"m very sensitive to this medication to be able to tolerate large doses. It's doing something slightly different in my body than it is in yours. Another too bad is you can't get urinary excretion tests done although that would give even more information. I would appear you are absorbing but the question is, what happens once it's in the blood.)

Did you feel okay on 100/20? The blood test results WOULD indicate that you SHOULD (by endo standards) be good. (Although I guess not if you increased T3 to 40 mcg........)

Too bad we can't have lunch and hash this through. :)


Gabkad, I think it's established that what's going on in serum isn't necessarily a reflection on what's happening at an intracellular level.

I felt comparatively well on 100mcg+20mcg for a couple of months but as I became more active I seemed to run out of steam which is why I increased T3 to 40mcg. When weather became very hot in June I decreased T4 to 75mcg as I struggled to cope and felt overheated with electric shock pins and needles in my arms and hands. I feel a little undermedicated on this dose and carpal tunnel symptoms resumed in left hand but are less irritating than the tingles. My hands and feet are icy since I reduced and the weather cooled (unseasonably cool for Aug since Bertha) so I may resume 100mcg any time soon.


Does high Free T3 due to pooling cause any problems with the ratio? Yes. You may have a better-looking ratio than you really have if you weren’t pooling. (Pooling means having T3 build high in the blood because it’s not getting to your cells—usually due to low cortisol, high cortisol, or low iron)



Marigold, it is a revelation when you find that you are not alone in your dis-satisfaction with your treatment and to be kept ill for more than 30 years (a lifetime) its a disgrace.

Well, I don't know the highest dose prescribed in the UK, but Dr Lowe in the USA (RIP) did prescribe high doses of T3 when the patient was resistant to thyroid hormones. A couple of excerpts:-

Synthroid contains the form of thyroid hormone called T4. Many hypothyroid patients, such as you, benefit little or none from its use, despite the brand they use. Cytomel contains the more metabolically active form of thyroid hormone called T3. T3 is effective for many patients who failed to benefit from the use of T4. (Synthroid is the USA levothyroxine)

Your doctor’s false belief about the use of T3 isn’t unusual. Many doctors believe that T3 is dangerous. When pharmacists fill prescriptions for Cytomel, however, they often give patients a leaflet that makes the safety of T3 perfectly clear. Verbatim, the leaflet reads: "NO COMMON SIDE EFFECTS HAVE BEEN REPORTED with the proper use of this medicine." (Medi-Span, Inc.: Database Version 97.2. Data © 1997.) When used with reasonable precaution, T3 is perfectly safe.

Doctors commonly prescribe a variety of drugs to control hypothyroid symptoms that continue despite patients’ use of T4. In stark contrast to T3, most of these drugs have long lists of potentially harmful effects. The safety of T3 use starkly contrasts with the risks of using the other drugs. Since this fact is well documented in the medical literature, I find it baffling that so many doctors falsely believe just the opposite.


To the discredit of both conventional endocrinologists and the thyroid specialists whose edicts the obey, this mandate is not scientifically based. Instead, it’s based on a powerful marketing campaign of a major pharmaceutical company. This marketing campaign, not science, is precisely why most doctors robotically write "Synthroid" on their prescription pads when they learn that a patient is hypothyroid. Conventional doctors, including endocrinologists, have allowed their minds to be utterly subjugated by this marketing campaign. As a result, they’ve deprived themselves of clinical experience with any thyroid preparation other than T4.

So, the wariness of conventional doctors, including endocrinologists, about the use of T3 is born of ignorance. Thus, as a whole, they are the least qualified doctors from whom to seek expert advice about T3. In the past several years, many unconventional doctors have acquired extensive experience with the use of T3. These doctors include many family physicians, physiatrists, psychiatrists, nutritional and holistic doctors, and naturopathic physicians. For expert advice about T3, it seems prudent to bypass endocrinologists and to look to these more knowledgeable and experienced doctors.

First, resistant patients recover from their hypothyroid-like symptoms and signs only with extraordinarily large dosages of T3 (called "supraphysiologic" dosages). Second, despite these large dosages—which might hospitalize a person who doesn't have tissue resistance—the patients have no indication of tissue overstimulation. (We use various objective tests to rule out overstimulation, such as serial EKGs and various biochemical tests. We also closely scrutinize patients and use various physical exam procedures such as the Achilles reflex test.) Third, although the patients have recovered from their symptoms and signs with high dosages that don't overstimulate them, lab tests show that they have extremely high blood levels of free T3.

If these patients did not have tissue resistance to thyroid hormone, the high blood levels of T3 would cause severe overstimulation (termed thyrotoxicosis). Hence, we know the patients' peripheral tissues are resistance to normal levels of thyroid hormone. Unfortunately, we don't know the mechanism of the tissue resistance. But we're determined to identify the mechanism through further studies.


Would like to push the recommend button more than once - :-)


Hi Marz, interested you wanted to click Recommend button more than once!! Wow - you have guest house in Crete. Do you have a website? Are you open for business in January, February, March?


Yes we are open all year - we have always been fortunate to have long winter lets over the last 9 years - however at the moment the Guest house is available for the months you mention. The problem is that people have to fly to Athens and then onwards to Crete as all the Budget lines only do the Summer season. We also have a the moment there are 4 Swiss in the Guest House and 2 from Berlin in the Studio :-) We are on Airbnb - Relaxing in Betsy - Vamos.... and Oleander...have a look....

I wanted to click more than once as the post was so helpful ....


I pressed it for you :D

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Ta :-)


I'm quite new to the site, so haven't heard many people's stories. But I can start the ball rolling with my high-ish dose. I've had my thyroid removed due to cancer, and I was started on 60mcg. My guess is that this is still a low-ish dose, as my experience is similar to yours, that doctors want me to be on as low a dose as possible. I was on that for about 8 months, and never got to a point when I was on enough T3 to really make a difference.


There are many people's stories written up on the main Thyroid UK site here:

60 micrograms is often regarded not as low-ish dose but as the maximum that doctors can prescribe. Whilst that is not true (they can prescribe what they think the patient needs), it often appears that medics don;t realise that they can prescribe more. At least one person here is (or was) on 160 micrograms. That, it must be added, is exceptionally high.


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My Endo would only prescribe a maximum of 60mcg which is no good for me. So far he's doing everything he can to avoid me being prescribed T3 on the NHS.

I really don't know how some of these people sleep at night knowing fine well that peoples lives have been turned upside down by self-serving NHS incompetence that our taxes have contributed to.


Hi there, I'm new here & it's helped me so much to read & learn etc. Noticed you post/reply often & you are obviously as enraged as me about the treatment we hypo patients receive. Today I looked at GMC's website.... & sat at my laptop laughing. I've copied one small piece ....

Quoted from GMC website .....

"Our values

We have four core organisational values which underpin everything we do.

Excellence - we are committed to excellence in everything that we do.

Fairness - we treat everyone fairly.

Transparency - we are honest and strive to be open and transparent.

Collaboration - we are a listening and learning organisation.

These values form the basis on which our organisation operates. We want every decision we make, every interaction we have and every email we write to embody our values.

Each of our actions demonstrates our character and beliefs as an organisation. It’s important that each member of our team acts in a way that's consistent with our values, and in a way that reflects the principles we believe in."

There's much much more there - eg concerning how doctors should behave & treat patients etc.

Surely a 'terrier style' QC could run rings around them? Particularly with all of our stories. Their website shows such hypocrisy.


The GMC run a protection racquet for GPs. GPs have to pay them an annual fee for training purposes.

All the GMC wanted to do was to defend the 3 GPs whom I reported to them for misdiagnosis. As far as they were concerned depression (the diagnosis of 3 GPs) and hypothyroidism are very similar. I sent them copies of blood test results where it was bloomin' obvious I was hypothyroid.

Yes, I would love to take legal action against them for misdiagnosis!

Agree with your comments about their website - it's been made 'fluffy' but it's absolute rubbish as they definitely aren't interested in patients' complaints.


If you haven't read the guidelines of the British Thyroid Association it would be worth a read, particularly their false claims about natural dessicated thyroid and T3. Also they state that only levothyroxine is the medication to be prescribed.

I would still be very unwell if I was taking levo.

Reply uch is your dose of T3? and the other question would be ..are you also taking Levothyroxine T4 ? If the answer is YES, tell me please how much dosis of both you take?..


For 15 years from being diagnosed very hypo, I was only on T4; felt incredibly ill. Dr P changed me to T3 only in 1995 (20mcg day). Then years later put dose up myself to 30mcg day & managed to argue my case. In April this year I begged an endo to increase to 40mcg day & fell human. Although I have changed my diet (orthomolecular nutrition) & take high dose supplements which were originally meant for osteoporosis (diagnosed in April 2014) but think diet & vits/mins have helped too. My thinking here is that for 3 decades my thyroid med was much too low.


Osteoporosis can occur due to not being given the correct thyroid medication although my Endo is claiming that mine has been caused by too much T3.

You really can't trust any of them.

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All three doctors, Dr Peatfield, Dr Skinner and Dr Lowe said that nowadays our medication is far too low which can lead to us having further more serious diseases and prescribed additional medication for symptoms rather than a decent amount of thyroid hormones. Also we are not medicated until our TSH and comes into a certain range and the UK's too high.

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Which supplements are you on marigold22? I am taking 118mcg T3 at the moment and was diagnosed with osteopenia a couple of years ago. I'd like to reverse it if I can but I have been concentrating on my thyroid and adrenals so it may be worse by now. Have you had any improvement in your osteoporosis?


I am on T3 only - the endo kind of washed his hands of me while writing to my GP and said she could try me on T3 only. That was just over a year ago. I kind of fiddle with the doses on my own (while keeping an eye on BP/HR etc), and using Paul Robinson's book initially. I am using at the moment around 55mcg.

Previously I was on T4 only for 18 yrs, and did a short trial of T4/T3 which made me feel worse (6 weeks). I was v surprised that the endo agree to the T3 only to be honest after such a short trial. I did try reintroducing some T4 earlier this year but ended up with horrendous knee pain so stopped.

The GP lets me get on with it pretty much alone, and even seemed reluctant to do blood tests as she said she wouldn't know what to do with the results! (Once said i knew more about the thyroid than she did...). I am just keeping my head down as you can imagine.


I had a very long fight with my Endo when I wanted to take T3 medication. In the end I refused to take T4 (as you are allowed to do ) and he had to treat my hypothyroidism with T3. He ran some tests to satisfy himself that it was not causing me heart problems but finally gave in and prescribed me 50 mcg per day. My GP has since upped this to 60 mcg but this is not enough to treat my hypo-thyroidal dementia. I now top this dose up with purchased T3 (50mcg) and have taken full responsibility for taking this dose off my GP. This now is holding the hypo-thyroidal dementia at bay and giving me a wonderful active life style. I keep away from my GP and avoid blood tests as he does not understand the results. I split the dose into lots of small portions throughout the day which works for me. For me, T3 is an absolute life saver!


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Sounds like you've had a big and long fight. I've never heard of hypo-thyroidal dementia.... It's obviously linked to low thyroid; and I think I'm a prime candidate. Could I ask you to private mail me with details of your T3 supplier. Best wishes


Message sent. Even the psychogeriatition that I am under is amazed that the T3 has had such an impact on my life and my dementia. Sadly i have lots of brain damage for the years that I had battling to get my thyroid and brain problems sorted but i'm making the best of it now! I had a low TSH for many years which decided to taper off to nothing after banging my head which must have damaged my pituitary. The Endos were no help what so ever but I found Paul Robinson on this site and when I read his book the answer was clear. I could only take T3 as I don't have a TSH .

Hope this helps.



Many people order their own T3. I take 35 mcg. now which is equal to about one and 1/4 grain Armour.


Heloise. Do you take T4 also? Also what is your TSH and T4 and T3? thanks


Hi Anuba, I haven't been on T4 for years and years. I was on Armour when I went on straight T3 because I couldn't get ideal levels. I went onto a 25 mcg. cynomel within a week and quit the Armour entirely. I was hoping to be able to increase it as I still have muscle issues. My TSH was 1.66 while on the Armour and FT3 and 4 were barely in range. After one year on T3 my FT3 is still too low:

tsh .438 0.450-4.500 uIU/ml

ft4 .11 0.82-1.77 ng/dl

ft3 2.8 2.0 4.4 pg/ml

Are you considering a change?


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