Thyroid UK
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Negative side effects from T3 (Tiromel) - any help much appreciated

I've been taking 50mcg of T3 for 3 weeks and have begun to get pretty bad stomach pain/nausea throughout the day. These symptoms go away when I stop taking the medication but then so does any positive effect it's been having.

Does anyone have any experience with this? I have tried taking at different times of day, lowering the dose, splitting the dose, etc. but to no avail. I stopped and restarted on 25mcg but the pain returned almost immediately.

Having searched online there doesn't seem to be much on this, so I'm hoping it might be the brand (Tiromel, from Cyprus) or one of its ingredients?

Less urgent although slightly concerning is that my heart rate also shoots up when having a hot shower, leaving me very light headed and feeling weak. This I'm assuming is related to the thermo-regulation properties of the thyroid, so T3 might be throwing that out of whack and subsequently sends my heart rate rocketing. Anyone familiar with this?

Any advice or help with this would be greatly appreciated. Many thanks.

PS. To my knowledge I am not hypothyroid. I've been diagnosed with Type II Bipolar and my main symptoms are chronic fatigue, depression and loss of cognitive function. My previous psychiatrist had me on a very high dose of T4, which didn't do much to help and began to give me negative symptoms (similar to those on T3) at around the 450mcg mark. I then tested positive for the defective DI02 gene, indicating I have a decreased ability to metabolise T4 into T3, and facing resistance to T3 from several doctors I decided to buy and administer it myself. Occasionally on T3 I have experienced some relief of symptoms (which to me seems to indicate there is something there) but the negatives usually outweigh the positives. In spite of this I am very keen for T3 to work as the next step seems to be antidepressants or worse. Again, if anyone has experience with any of this I'd really appreciate any advice.

24 Replies

Hb8847, The studies I've seen use T4 or T3 as adjuncts to antidepressants in cases of drug refractory depression not instead of antidepressants.

Some members will self medicate to resolve hypothyroid symptoms but they are advised to check thyroid levels with blood tests to ensure FT3 remains within range. Long term FT3 over range increases the risks of developing atrial fibrillation and osteoporosis. This is one of the reasons endocrinologists don't support psychiatrists' use of thyroid hormone in euthyroid depressed patients.

Your symptoms sound like overmedication and I would be concerned about the heart rate shooting up. Thyroid hormone should be titrated gradually and 50mcg T3 is a high dose to be at after 3 weeks. If you intend to continue taking T3 I would recommend thyroid tests to check levels and ensure FT3 is kept within range. A smaller dose of T3 split into 2 or 3 doses will aid T4 to T3 conversion and may help with depression and cognition without causing stomach pains and increased heart rate. You can order private thyroid tests from Blue Horizon and Genova via

It's possible you are reacting to one of the fillers in Tiromel and another brand of T3 might suit you better but choices are limited with, and without, a prescription. I personally find Tiromel and UK Liothyronine to be very similar. Many members like Mexican Cynomel but this won't be available before November, if then. US Cytomel is expensive at $258 for 100 x 25mcg.


Thank you for the advice Clutter


Any adrenal problems? Hot water makes your pulse/heart rate rise when your BP drops as the blood vessels dilate. See also

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No adrenal problems that I know of, but thank you for the info as most of these symptoms are relevant to me. Overmedication on T3 is probably throwing my adrenals off kilter.


Have you cut out gluten? For some people there is a relationship with gluten and what is called bi-polar. Diet can have a strong effect on the brain. You might find Dr. Brogan's work interesting. I think the shrinks normally use high T4 with bi-polar and high T3 with major depressive disorder. They are experimenting, they don't really have a solid understanding of what is happening and exactly what is out of balance. PR


Thanks a lot for your response PR, bizarrely I read an article about gluten last week and cut it out immediately. My symptoms are mainly unchanged since then, perhaps unsurprising given the lack of time that has passed. Do you know how long it should take for it to exit my system and/or symptoms to improve? I'll check out the website now. Thanks again.


As in all things in the human body 'your mileage may vary'. Some notice a difference sooner than others but I would suggest a minimum of 2-3 months before reaching any conclusions. Then try adding some back to see if you get a reaction. In reality we understand so little about what is actually happening in the body. If I remember correctly gluten can cause an increase in cytokine levels which affects the brain. Good luck. Other food sensitivities can also contribute. PR


PS Are you a C-section baby? Also people can vary considerably in how quickly or slowly they can increase their dose. Some people need more time for their body to adjust between increases. PR


Hi - sorry to hear your experiencing problems with Tiromel, it could be one

of the non active ingredients that is upsetting you. And I'm not sure

T3 itself at the right dose would have that effect on heart rate. I am

interested to know if your in UK &, if so, where you had the Gene Test

carried out ?


I am based in the UK yes. The gene test was done via Regenerus Labs.

Regarding T3, I'm very confused by the negative effect it seems to have on my system, especially since the gene test would indicate my cells would benefit from a bit more. I've also seen nothing related to stomach pain online, the first symptoms people mention seem to be heat intolerance, perspiration and tremors, none of which apply to me.


Hb8847, you haven't mentioned diarrhoea with the stomach pains but it is a common over medication symptom.


Haven't had any of that Clutter but thanks for the info. I think I might come off the T3 entirely for the time being.


Just noticed 50mcg T3 ! I agree it seems a high dose & whatever you

take, have you tried divided doses as mentioned above. I think

if you search under Tiromel on here, you might find some answers.


Hello Hb8847,

I'm sorry to hear you feel so unwell and are not receiving professional helpful medical support and guidence.

T3 should be introduced slowly so maybe you have had too much too quickly.

The heart palpatations would substantiate this.

I am not familiar with the use of thyroid meds treating bipolar but know that all hormones work in synergy and taking such large amounts of one when there is no deficiency could lead to massive inbalance throughout the whole endocrine system. 450 mcg was a very high dose of Levo and so could well have previously been responsible for elevated reverse T3 causing your negative symptoms. Maybe a better mix would be a combination of a much lower dose of both T4 and T3

A good read is " Why Isn't My Brain Working" where Datis Kharrazian explains the workings of the gut-brain axis and the action of various drugs and supplements.

He explains how the brain has its own nervous system called the "enteric nervous system" which communicates to all organs including those in the digestive tract.

He also explains how thyroid hormones work and the possible results of too much or too little of various hormones.

Gluten is the protein fraction of wheat and if intolerated, causes the body to produce an antibody by a process of molecular mimicry. This antibody cross reacts with thyroperoxidase enzyme which is responsible in the production of thyroxine. If you find cutting out gluten hasn't made a difference, then you probably aren't intolerant of gluten.

I take T3 and split the dose.

Do you have recent thyroid hormone test results that you can post in a new question?

I hope you find your answer soon,



Thank you for the advice, Flower007, and the book looks very interesting.

My blood test results when not on medication are as follows.

TSH 1.89 (0.35 - 4.94)

FT3 4.78 (2.63 - 5.70)

FT4 14.1 (9.0 - 22.0)

Regarding gluten, I'm yet to notice a change as I'm only 2 weeks into a gluten free diet but perhaps thats to be expected. I'm also going dairy free just to cover all bases.

Thanks again.



You are definitely not over medicated so Clutters advice about

a possible reaction to a filler might be worth considering (see above).

I would say your TSH is too high and there is room for improvement on both T3 and T4 warranting a med increase. However, it would be beneficial to you to repost your results in a new question for more experienced people than me to also comment.

You don't need to rewrite all history as members can check your previous posts by clicking on your name.



I think you may have misunderstood, these test results are from when I was not on any medication, so they wouldn't reveal whether I'm currently on too much T3.

I don't know my current levels as I'm not seeing a doctor for regular check-ups, but I'd imagine my levels are way above range given that I'm otherwise euthyroid. Being above range doesn't concern me too much as there doesn't seem to be much evidence that it's harmful to euthyroid patients, I'm mainly going on side effects.

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Sorry, I did misunderstand hb88847,

Only recent thyroid hormone blood tests are relevant in diagnosing an under or over medication problem.

Testing is important to assess your T3 levels are not over range as this can lead to atrial fibrillation and oesteoporosis.

Also, the following link states......

" incorrect doses or excessive doses of T3 may produce symptoms of thyroid storm in sensitive people. This is a potentially life-threatening condition produced when there is too much T3 thyroid replacement hormone in the body. Thyroid storm symptoms according to are overly fast heartbeat, excessively high blood pressure, extreme restlessness, confusion, extreme anxiousness with irritability, shaking diarrhea, nausea, coma or shock.



Thanks again for the info Flower007. I will keep an eye out for the symptoms but currently I'm only experiencing minor discomfort and have decided to stop medication for the time being.

As for atrial fibrillation and osteoporosis, my understanding is that these are more of a concern if the patient is hypothyroid. High dose thyroid (HDT) medication is often used on euthyroid patients with bipolar type illnesses and, whilst this pushes the T3 and T4 levels way above range, it does not carry the same risks on the heart and bones as for hypothyroid patients. Nevertheless I will look to get these checked regularly if I end up taking thyroid meds long term.


Maybe you should try introducing the T3 more slowly. 50mcgs is a whacking dose for your body to cope with. Self medicating is fine. Many people need to do that but one should always err on the side of caution maybe follow guidelines as to how quickly these meds should be raised.

I'm very drug sensitive and have to raise very, very slowly. I raised my T3 by 5mcgs every 2 or 3 weeks and even then had times when I had to drop back. Listen to your body.

Please get your bloods done to check levels. T3 is a very safe drug when used properly but that means PROPERLY. Rushing things will not improve the situation.

It's a shame that antidepressants have gained such bad press. For many people they are a life saver but negativity towards them has lead to fear and mis trust.

Did you ever have a thyroid panel run before you were put on any form of thyroxine? It would have been interesting to see the levels.

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I'm finding Tiromel to be considerably weaker than Cynomel and have increased my dosage.

Will be looking around for an alternative.

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I too found Tiromel weaker cinnamon-girl. Apart from the obvious, any ideas where to look? Thanks Bev.


Beverleyb- depends on how rich you are! I'm unable to spend £100 per month on T3 especially when the NHS should be prescribing it. I think one needs to be careful with suppliers, worth looking at the Ray Peat forum for useful info.

Has your health become worse with Tiromel?


Not rich at all cinnamon_girl, ha,ha, I couldn't afford £100 a month, and as you say, why should we! I was taking Armour and 12mg Tiromel, but I used to fall asleep after taking them. T3 I got from GP was better. Im going to start taking Nature Thyroid when they arrive. Thanks for info I will have a look.

Regards Bev.


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