Hello, I've been on 75 mcgs for T3 after not having success with NDT or T4. My doctor wants to start lowering my dose because of the risks to my heart and bone loss. But even at this dose, I'm having hypo symptoms. I've gained 25 pounds since February, despite doing an hour of cardio six days per week, and eating a balanced moderate calorie diet. I'm losing body hair, and I barely have the energy to get out of bed on a regular basis. I read that high doses of T3 over a long period of time can cause T3 receptors to shut down. Does anyone know if there is any truth to that? When I first started T3, it worked very well. I felt great, and the weight just fell off, but now... I'm in the process of switching doctors. First doctor had me on just T4, and dismissed me when I told her I felt terrible, had gained 30 pounds in one month at one point, and was suffering from severe lethargy, and brain fog. Her response was, " your labs look fine." My current doctor had me on T3/T4 for a while and switched me to T3 only. And like I said, it worked well for about a year, and as my symptoms returned, he just raised the dose. Now I'm looking for a doctor that will do more than run thyroid labs to find out why my body isn't utilizing thyroid meds properly. I'm wondering if I've been on too high of a dose of T3 for too long, and it's "burned out" my receptors. Is that a thing? Besides an issue with my receptors, which may not be a thing, where else should I be looking? So far, the things that I've checked are folate, and vitamin D which which are low and I'm addressing. I also have high diurnal cortisol, and high ferritin. The high ferritin may be due to inflammation. I have rheumatoid arthritis, and present TPO antibodies. Iron is normal. B12 is high. Thanks in advance!
Do high levels of T3 have to potential to shut ... - Thyroid UK
Do high levels of T3 have to potential to shut down T3 receptors?
Some folks need t4 as well. Some need a low dose of levo and others a high dose. So that folks on here can comment we really need recent blood results and ranges. There are folks on here who are t3 only and may offer pointers
Could you post your FT3 levels (together with lab ref ranges) please? Your doctor may be reacting to suppressed TSH which in itself doesn’t cause bone or cardiac problems.
Any other blood test results (with ranges) would also be helpful.
Hormone receptors can become less responsive or reduce in number when there are high levels of hormone. This usually requires hormones to be orders of magnitude above normal levels. As a real example I was on 105 mcg liothyroine (L-T3) for many years, I am now on 40 mcg which equates to about 120 mcg levothyroxine (L-T4). So, my receptors are working fine.
It would help to have some more information. What were your blood test results when you were started on thyroid hormone and what they are now? Also, what are your signs and symptoms when your were diagnosed and now? When did you first become hypothyroid and were there any changes in your life at the time? e.g moving to a new job or house.
Endocrine disrupting chemicals (EDCs) can cause disruption of thyroid hormone action on receptors. The USA has very high levels of EDCs, particularly in California and the Great Lakes areas. This is why I asked about changes to your job or home.
Your weight gain is quite exceptional, very rapid which is diffcult to explain. Are you on any other medicines and have you been tested for diabetes?
Please note I'm a fellow patient not a doctor.
I was on 225 mcg T3 only for some time (can't remember how long, memory shot), then - for various reasons I won't go into, came off it for a few months - then went back onto 75 mcg (working up slowly from zero). And 75 mcg is now exactly what I need. Any more makes me feel bad, as does any less. So, I imagine that my receptors have improved since the days of 225 mcg, and are no working as well as they're ever going to work. 
Hi greygoose!! Im on 225 and feeling bad. For a long time it felt like the perfect dose but now my heart is racing and I feel horrible. I want to stop. Did you quit 225 cold turkey? Did you gain a lot of weight as a result? I would love to stop it completely, and maybe go on a lower dose thereafter (after a few months). Would love to hear your experience with this xoxox
I'm afraid it really wasn't as simple as all that, and I'm loath to go into details. But, I didn't stop it because I wanted to reduce my dose, I did it because I was ill and not even capable of thinking what I was doing. And, no help from medical sources, of course! I would advise you to reduce slowly, 6.25 mcg every two weeks. Monitor your responses throughout, and stop reducing when you feel well. I cannot advise you to just stop taking your T3 completely for a few months.
Hi, and thanks for the replies. When I was first put on T4, my levels were as follows
TSH 4.020 uIU/mL Range (0.450 - 4.500)
Thyroxine (T4) Range (4.6 ug/dL 4.5 - 12.0)
T3 Uptake 34 % 24 - 39
T3 and RT3 weren't tested. The first doctor I spoke to sent me on my way because she said my labs were within range. I had started taking gabapentin 8 months previous to getting my thyroid tested. Unfortunately my current doctor only ordered TSH for my most recent test because he says that's the only thing that matters, TSH 0.16 mU/L Range (0.27 - 4.20 mU/L) But other tests that were run are as follows.
Thyroid Peroxidase (TPO) Ab 12 IU/mL Range 0 - 34
Iron and TIBC
Iron Bind.Cap.(TIBC) 329 ug/dL 250 - 450
UIBC 227 ug/dL 111 - 343
Iron, Serum 102 ug/dL 38 - 169
Iron Saturation 31 % 15 - 55
Ferritin, Serum 479 ng/mL 30 - 400
Transferrin 248 mg/dL 200 - 370
Folate7.0 ng/mL 7.3 - 26.1
Vitamin Total 25 Hydroxy 27 ng/mL 21 - 70
The biggest issue I was having when I went in was the inability to lose weight, and eventually weight gain, despite regular exercise and a healthy diet. I eventually started suffering with constipation, extreme lethargy, brain fog and body hair loss, all of which I am currently suffering from. I also had a glucose test done. 93 mg/dL (70 - 100 mg/dL)
Hopefully this additional information is helpful.
You really need to see a full thyroid panel to make evaluations about thyroid hormone. Your doctor is probably a bit of a blockhead, as many are, going by TSH only. You may need to order your own private tests. If you're in the US Stop The Thyroid Madness website has suggested ways to get it done.
your folate and vitamin D are both extremely bad. These need to be worked in urgently, and will be causing symptoms and problems. These vitamins are required for thyroid hormone to work properly, so improving them will get you at least some of the way to doing better on hormone. You're right that the high ferritin suggests inflammation. Iron doesn't look too bad, but I don't know enough to really comment.
Being hypothyroid, especially for a long time, trashes our vitamins. The fact yours are so bad does make me wonder if your dose has been too low the whole time. But we can only really comment once we see the blood tests.
Exercising and restricting calories is also very hard on the body while hypothyroid. A decent level of calories is needed to use the hormone fully, and exercise uses up our T3. You might find that if you cut your exercise, and add some fat to your diet if you're currently low fat, you will feel a lot of improvement and may lose weight again.
You might be surprised at how low your vitamin D level actually is. Mine was only 23 (30 - 100 ng/mL) when I was first sent for testing. Yours is "in range" but nowhere near sufficient for good health. You might also be surprised at how much supplemental vitamin D you need to take to get your serum levels of 25 Hydroxy up into a healthier level. vitamindcouncil.org/about-v...
The Vitamin D council says:
"The symptoms of vitamin D deficiency are sometimes vague and can include tiredness and general aches and pains. Some people may not have any symptoms at all.
"If you have a severe vitamin D deficiency you may have pain in your bones and weakness, which may mean you have difficulty getting around. You may also have frequent infections. However, not everyone gets these symptoms."
This page provides information on how much vitamin D you need to take to go from a current level up to specified levels. vitamindcouncil.org/i-teste...
According to most standards, including the Vitamin D Council, Endocrine Society and Institute of Medicine, you are getting enough vitamin D if your level is between 40 - 50 ng/mL. Due to a history of cancer, I am aiming higher. cancer.gov/about-cancer/cau...
grassrootshealth.net/grassr...
BTW - When taking Vitamin D, it is important to take it along with co-factors: Vitamin K2 MK-7 helps Vitamin D route the calcium in your body to bones and teeth instead of to soft tissue such as blood vessels and breast tissue. Magnesium also helps for this purpose.
And as for the constipation you mentioned, Magnesium can help take care of that. Here is a guide to the capabilities of the various types: vitacost.com/blog/vitamins-...
NOTE: Avoid magnesium oxide due to low levels of bioavailability. Magnesium citrate is a good choice to alleviate constipation, but don't overdo it. For general supplementation, (e.g. to assist in getting calcium to bones and teeth) and for relief of stress, magnesium glycinate is good, and it's not known for laxative effects.
Are you still taking gabapentin? It can cause dramatic weight gain in some. It acts on the nervous system so might cause problems. It was prescribed to me many years ago and I was not able to tolerate it.
Your folate is low. Perhaps could be leading to some problems.
Hi, is it possible for you to get tested privately for your T3, I think it would be useful to see that? I take it you are not having symptoms of hyperthyroidism? Palpitations etc. Where are the B12 results- what do you mean by high and is this high naturally or high with supplementation?
It looks like your folate is too low and your vitamin D could be improved. I wonder if you need to look at other co factors such as selenium and supporting your conversion and adrenals.
What is interesting is the comment above re Gabapentin and weight gain. RA- look at taking turmeric, frankincense, a little chilli for pain and inflammation. Perhaps Devil’s claw. Astragalus.
Look for a herbalist to put together a great formula just for you and care for you holistically.
Hi,
I've just read a very interesting article on testosterone levels related to the under diagnosed testosterone issues... I'm sorry I don't know your sex, but as there are considerable similarities between menopause and what is increasingly being thought of as the 'andropause', a few things you mentioned have sparked my interest.
The article describes how low sex hormones can be the cause/ contribute to fatigue, weight gain, depression, thyroid issues, loss of body hair etc...so given the similarities, I thought it worth mentioning, as nothing is cut and dry and our collective illnesses are certainly not 'linear' in their manifestations of progression!
It's an interesting read.
It's another piece to this three dimensional muli-puzzle that plagues us all with I'll health.
Good luck.
Best Wishes
Poppy the 🐈
Oh, B12 was 1,523 pg/mL211 - 946 pg/mL. I'm not sure what was going on there, as I don't eat a ton of high B12 foods, or supplement. I may have to get that retested. I have found a lab here in the US where I can get testing done out of pocket. Wish me luck.
Look at getting your adrenals checked. Loss of body hair is common with addisons, do you have any hyperpigmentation of skin?
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