Supplementing with t3: Hi, I was diagnosed with... - Thyroid UK

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Supplementing with t3


Hi, I was diagnosed with autoimmune hypothyroidism 12 months ago and feel like it was the beginning of the end for me. Since being diagnosed my life has basically fallen apart. I have even considered suicide. I reached out for help and have been totally let down by the medical profession. I have no energy, I ache all over, I have gained 4 stone in a year and I am severely depressed. I am on a number of antipsychotics, which in themselves are giving me side effects. In terms of thyroid medication, I am taking 150mgs of Levothyroxine daily. My tsh is 0.09, my t3 is 3.8 and my t4 is 15. I pushed my gp to refer me to an endocrinologist who basically told me that none of my problems were thyroid related. I just don’t want to live my life like this anymore. Would supplementing with t3 help?

13 Replies


To be able to tell you if T3 will help, we need to have the reference ranges for your results please. That will tell us how well you convert T4 to T3.

Also, for thyroid hormone to work properly, we need optimal nutrient levels. You need the following tested, and it's essential to test them before considering T3:

Vit D




As you have autoimmune thyroid disease aka Hashimoto's, are you addressing this with a gluten free diet and supplementing with selenium l-selenomethionine 200mcg daily to help reduce the antibodies? It's helped many members here, and you don't need to be coeliac for a gluten free diet to help.

Do you take any other medication or supplements? If so, what? Levo should be taken at least 2 hours away from other medication and supplements, some need 4 hours.

Unfortunately you have not put the various ranges for TSH, FT4, FT3 , what lab did the blood tests? It is difficult to comment without them.

Really need to see the reference intervals for these results but if they are typical your TSH is too low for the fT3, fT4 levels you have. This leads to low fT3 levels because TSH stimulates a form of T4 to T3 conversion called 'type-2 deiodinase' which is expressed in the brain and some other tissues. Consequently it's not surprising you feel terrible. It may well explain your depression. However, depression can also cause this low TSH so it's not easy to identify the underlying problem. It's a bit 'chicken and egg'. Nonetheless, I feel that some liothyronine (L-T3) would probably make a big difference (I'm a patient not a doctor). It would seem reasonable to introduce 10 mcg liothyronine initially (quarter tablet at breakfast and bedtime) and then gradually increase the liothyronine whilst reducing the levothyroxine. Once you start to feel better you could start to try and wean yourself off the antipsychotics.

It would be better if you could get this treatment from a doctor. I would actually try the endocrinologist who refused you treatment. Perhaps send a letter saying you feel they haven't taken account of your low fT3 and abnormally low TSH and you want to try some liothyronine. Explain (briefly) the devastating effect on your life and you feel it would be negligent to overlook a potential solution and you really do not want to resort to self-treatment. They may well refuse but all you have to do is write a letter and it seems a shame to let them off the hook too easily.

If they refuse you can seek out a different doctor or resort to buying liothyronine yourself.

Get hold of the reference intervals and post them here. Also, ask for a copy of all your blood test results. It would be useful to know what your results were when you were first diagnosed.

roxanaleah in reply to jimh111

I'm uncertain as to your meaning, entirely. But if you are suggesting the possibility of overmedication, then not only do I concur, in the strongest terms, but I congratulate you on the courage to make it on a forum I consider extremely biased toward recommendations of medication increases.

In fact, I have been quietly experimenting for months, with dosages (after having come down from an all-time high of 75t4/15t3 [a dose I cannot believe I was ever taking!]) and I can attest to the fact that, like clockwork, one of the first symptoms of overmedication I experience is fatigue, coupled with an inability to think straight. I believe reports of the "overlap" of symptoms are greatly understated. I also believe that the mechanisms of thyroid-pituitary-regulation are not wholly understood, even by 'experts'. What's more, as lay people, who likely never gave the thyroid gland a moment's consideration before we were diagnosed, I believe our symptoms present us with unfortunate counterintuitive truths that cause us to mistakenly and continually increase our doses.

After nearly two years of chasing the elusive proper dosage, I weaned down to a fraction of my original dose and the two most undeniable results were a clearheadedness I thought was gone forever and multiple hours of continuous sleep.

Only desperation could have led me to try reducing my dose when all of my symptoms screamed, "undermedicated".

But, since being diagnosed with Hashimoto's, it is the best thing I've done relative to my thyroiditis.

jimh111 in reply to roxanaleah

Sorry, I'm not suggesting overmedication. An fT3 of 15 on levothyroxine is not overmedication (assuming a typical fT4 reference interval of 10.0 - 20.0). On levothyroxine only therapy fT4 needs to be around 18.0 to compensate for the absence of T3 from the thyroid (secretion and deiodinase) and bring fT3 to average levels.

For patients without a healthy thyroid levothyroxine only therapy leads to reduced T3 levels. This is due to three effects. 1. Loss of thyroidal secretion of T3. 2. Loss of thyroidal deiodinase (conversion of T4 to T3). 3. As levothryoxine doses are titrated up it lowers TSH which reduces peripheral type-2 deiodinase. Many patients do well on levothyroxine only therapy in spite of these disadvantages. Perhaps their health is not perfect but they are generally well and happy with their condition. There are many patients with severe hypothyroidism that we need to focus on.

I fully agree that thyroid pituitary regulation is poorly understood. There have been some outstanding advances made by a team who are also advisors to Thyroid UK. Their research is available for free here . Unfortunately you need to have a lot of expertise to follow this document, sometimes great science is not easy to follow.

For a patient to be well with normal fT4 levels they need an appropriate TSH. If the patient has normal thyroid hormone levels and a low TSH they will not convert T4 to T3 appropriately. Type-2 deiodinase (D2) is reduced. This leads to reduced fT3 levels but more importantly organs that rely on D2 activity (including the brain) are rendered hypothyroid. This appears to be happening in JBLOVELL's case which is why they may do better with some liothyronine.

Looking at one of your earlier posts this may be happening in your case. (please raise a separate post if you want to discuss). When you see an average fT3 in a person not taking thyroid hormone most of this T3 has come from D2, it has come from the organs that rely on D2 activity. If a person has a low TSH and lowish fT3 simply replacing the missing T3 will not work, their corrected fT3 is not coming from D2 dependant tissues and the patient needs extra T3, which may be too much for tissues without D2 activity. In your case it may be that stopping or reducing your thyroid medication allowed your TSH to rise and you felt better because this allowed more D2 activity. In these sorts of cases the patient needs more L-T3 and less L-T4. It may be that in your case you autoimmune hypothyroidism and you are going through a period of hyperthyrodism, hormone levels can jump around in autoimune hypothyroidism.

Hidden in reply to roxanaleah

There seems no overmedication in this case because thyroid levels are still too low in spite of TSH being low as well.

JBLOVELL in reply to Hidden

Could you have a look at my blood test results please? I have added them to my original post. I just don’t know how, or even if I should, add in t3 and reduce t4 and in what doses. Thank you

Hidden in reply to JBLOVELL

Sorry, have no experience of T3 medication. Hopefully others will help, jimh111 gave good advice and knows a lot more than I do. I have some idea of how to read thyroid results and what they mean, but not much more. So far I haven't taken T3

JBLOVELL in reply to jimh111

Hi, I have added photos of my blood tests if you wouldn’t mind taking a look. Thank you.

jimh111 in reply to JBLOVELL

The reference interval for fT3 used by the lab is a bit different from most others so your fT3 is not bad. Your TSH is still lower that expected. This might be due to fluctuating thyroid hormone levels, TSH responds more slowly that fT3. So, my earlier comments still apply but to a lesser extent.

It may be that the antipsychotics are causing you to gain weight, I know this can happen but I've no knowledge in this area at all. It would seem that they should sort out your antipsychotic medicine, perhaps use just one drug and double check that none of them interfere with thyroid medication.

JBLOVELL in reply to jimh111

The weight and depression came before the antipsychotics. I really don’t know what to do. Would taking a t3 and t4 combo lower my tsh to a dangerous level?

jimh111 in reply to JBLOVELL

It's high fT3 and fT4 that would introduce risk as I believe in your case your TSH is underperforming, so TSH isn't a good marker for thyroid status.

JBLOVELL in reply to jimh111

Thank you so much for your advice.

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