Hi I’ve been taking T3 for well over a year along side T4. I felt great for a while and now I am back to a pattern of sleeping and feeling fatigued. No energy to do anything. I have been reading that people can habituated with T3 and should stop taking it for a while. This makes sense to me as why would T3 just stop working. Does anyone have a similar experience. Can you get habituated to T4 also? When I felt good my does of T4 was 64mcg and T3 5mcg 3 times day. I am in the process of experimenting leaving off T3 for a few days. Any advise greatly appreciated.
T3 Habituation: Hi I’ve been taking T3 for well... - Thyroid UK
T3 Habituation
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Biddy51
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TiggerMeAmbassador
"I have been reading that people can habituated with T3 and should stop taking it for a while"
That's a new one on me! Perhaps you could share where you have read this?
It could be that your dose is either too high or too low now you body has adjusted
I really wouldn't recommend going cold turkey as this could really mess you up and cause a crisis, have you got your latest full thyroid panel results? I'd also recommend getting your vit's and min's checked out as it could be low iron, B12, Vit D or folate causing these symptoms
This is absolute rubbish. Where on earth did you read that? It's like saying you can get used to oxygen and should try giving it up for a while.
T3 is a hormone, not a drug, and you can't live without it. Would you tell a diabetic to come off his insulin for a while so it doesn't become a habit? How can that make sense? It hasn't stopped working. It's hormone. Hormones don't just stop working, by themselves, they will always do as much as your body allows them to, but possibly something else has changed.
If you felt well on T3 for a while and then less well, it's not because you've 'got used to it' - a healthy thyroid makes T3 in a decent quantity, all day every day - it's probably because you're not taking enough and you're ready for an increase. But if you carry on with what you're doing, you risk making yourself ill.
T3 is the active thyroid hormone, needed by every single cell in your body to function correctly. But for it to do what it's supposed to do you need to take the exact same dose every day. So, if you don't take it every day, the little you are taking won't have much effect. Ask people who've had their T3 stopped by their doctors how they feel and what they think of this idea.
Thank you for your response. I am finding it all very unnerving with my symptoms of fatigue returning. My T4 that I take has only ever been 75mcg until taking T3. My Endo looked at my last four sets blood tests the year before last and said I wasn’t converting T4 to T3 very well. T3 was added slowly. My dose was increased to three times a day 5mcg. Sometimes if I don’t get the split of the tablet right I will get palpitations, so I know i’ve taking slightly too much. If I take less that quarter of a tablet I don’t get palpitations. So I guess T3 dose is correct. My endo has said he can still see T4, so I guess it’s still be being made to some degree. I am due blood tests soon, so will get them done. Supplements I take. Iron bisglycinate, Evening primrose oil, Omega 3 fish oil twice a day. D3 & K2, Selenium, Magnesium malate am. B complex, pro biotic & pre biotic, full spectrum amino acids, Lipasomel vit C, Vitamin A, zinc pm, Magnesium taurate pm, ashwagandha pm, curcumin pm, ginger root pm, vit C pm, B12 pm. Before bed Collagen, & L glutamine. I have sent off to see if I have the DIO1 & DIO2 genes. Thanks again for your response I do appreciate it. Have started with T3 again this morning.
That’s an enormous amount of supplements
Not generally recommended to supplement vitamin A
Don’t take iron without getting full iron panel including ferritin 3-4 times a year
It’s possible to have low ferritin but high iron
Test early morning, only water to drink between waking and test. Avoid high iron rich dinner night before test
If taking any iron supplements stop 3-5 days before testing
Medichecks iron panel test
medichecks.com/products/iro...
monitormyhealth.org.uk/anae...
Test vitamin D twice a year
Stop B complex or any supplements containing biotin 5-7 days before ALL blood tests
My endo has said he can still see T4, so I guess it’s still be being made to some degree.
The T4 he can 'see' is the T4 you're taking. Do you have your latest blood test results? If so, post them here, with ranges, and let's have a look.
As SlowDragon said, that is a lot of supplements! Do you really think they're all helping? It must take you ages to swallow them all! I think if it were me, I'd be having a serious thought about them all and possibly starting an 'elimination diet' sort of thing to find out which ones I really need, and which are costing me money unnecessarily.
That sounds like dangerous advice to me and possibly relates to something addictive like codeine....not to T3
T3 is a replacement thyroid hormone essential to the functioning of the body
It is possible to be over or under replaced with T3 but not "habituated" to it...habituated has a negative implication!
Did this info come from a body building site where T3 is used wrongly by bodybuilders to boost metabolism....it's possible that potentially dangerous use may become habituated.
In correct medical use T3 should be taken consistently in the correct dose. To stop taking it every so often would disturb what should be a constant supply of hormone to the cells, and so be detrimental to your health
Your "experiment" is not a wise one and will potentially make you unwell...don't do it!
I doubt T3 has stopped working but rather that you need to revise your dose....
So, have a full thyroid test to include....
TSH, FT4, FT3, vit D, vit B12, folate and ferritin....and thyroid antibodies TPO and Tg, if not already tested
Those new results will help point to the correct dose you need....post them if you wish advice from members
Be careful what you read....only use reliable sources!!
Is there a reason you don't advocate for testing RT3?
jayde7 I didn't mention rT3 for the these reasons....
The following wise words from our late SeasideSusie
Don't bother with reverse T3 testing, it's a red herring, costs a lot of money and takes quite a long time to get the results. Testing rT3 can tell you if your level is high but it can't tell you why it's high. There are many, many reasons for high rT3 but only one of them is to do with the thyroid and that's when there is an excess of unconverted T4 and you can tell that by looking at the FT4 and FT3 levels.
The view of Paul Robinson...
RT3 is only a guide and has to be put into perspective with patient symptoms and signs being the most important focus, along with how FT3 changes with changing treatment
I don't see the point of paraphrasing these already explicit texts!
I hope this helps.
SlowDragonAmbassador
more likely you need dose of levothyroxine increased
64mcg (odd dose) is very low dose levo
suggest you get FULL thyroid and vitamin testing asap
Exactly what vitamin supplements are you taking
Recommended that all thyroid blood tests early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
T3 ….day before test split T3 as 2 or 3 smaller doses spread through the day, with last dose approximately 8-12 hours before test
Private tests are available as NHS currently rarely tests Ft3 or all relevant vitamins
Post all about what time of day to test
healthunlocked.com/thyroidu...
Testing options and includes money off codes for private testing
Medichecks Thyroid plus BOTH TPO and TG antibodies and vitamins
medichecks.com/products/adv...
Blue Horizon Thyroid Premium Gold includes BOTH TPO and TG antibodies, cortisol and vitamins
bluehorizonbloodtests.co.uk...
Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee
Only do private testing early Monday or Tuesday morning.
Tips on how to do DIY finger prick test
support.medichecks.com/hc/e...
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
PLEASE don't stop your T3 right now! You will mess things up worse, and it may take a lot of time and effort then to resolve and get back to being well.
1st step - go to GP or private tester and get full basic tests: TSH, T4, T3, Vit D, B12, Folate, Ferritin. Treat this as urgent, and while your intake of T3 and T4 remains the same. NEVER come off your thyr meds without testing first - the problem may not be where you imagine.
Your Dec2023 test result only showed TSH T3 T4, and you were near bottom of the range for T4 then. You MUST check those vitamins - if they're not optimal, guess what? You'll feel tired and poorly, and all the T3 you're taking wont be able to work properly.
Once you've got up to date results, post them, and you'll get great advice and input.
Thank you. I have re started my T3 this morning. Will get bloods done asap.
SlowDragonAmbassador
Many people on Levo plus small doses of T3 find they need BOTH Ft4 and Ft3 at least 60-70% through range
Your last post showed Ft4 was only 3% through range
I can see that B12 testing is being advised, but as you are supplementing there is no point. You need to wait around 4 months without taking it to get a true result.
According to TheB12society.com:
'You need to be CLEAR of any any supplements containing vitamin B12, and/or foods and drinks with unnatural levels of B12, such as those fortified with or containing concentrated levels of B12 for AT LEAST 4 MONTHS BEFORE TESTING SERUM B12.' theb12society.com/diagnosing
With due respect to the expertise of the B12 Society, I don't think their testing scenario is well-fitted for those of us who are already hypothyroid and supplementing vitamins. I've been supplementing Bs for a few years but recent tests showed I am currently at deficiency levels for B12 and folate, and I have been feeling rotten, mentally and physically. I am awaiting more tests, and meanwhile am on 1000mcg sublingual B12 plus 2 x Vit B complex daily, for over a month now. I have a little more physical energy and my mind is functioning a bit better now. The idea of not taking ANY B12 for 4 months! fills me with dread.
The Society may need to expand their guidance which seems useful only to the undiagnosed.
I'm both hypothyroid and B12d. My GP told me that my B12 was rock bottom and advised oral supplementation despite many symptoms and a very healthy diet which would be expected to provide sufficient B12 naturally.I was so ill due to my undermedicated thyroid condition and also B12d I just did as I was told. I took supplements and ate fortified foods, and had 2 more B12 tests with my doctor claiming that I was on the mend as my results slowly lifted. My symptoms did not improve.
Fortunately I read advice on here that made me question the status quo. I have since refused all testing, because the results were misleading, and moved onto self treatment with injections. Then I tackled the GP with my evidence of improved symptoms.
I hope that you get adequate treatment soon.
You did a wise thing with the b12 injections. I took a high quality b12 from BSupps but it did nothing for me, zero, whilst others report having a good energy boost. Used an injection which worked quite well so some folks have very poor absorption with b12 as did I. Currently have an injection once a fortnight.
There is an acknowledged (not by most GPs of course) link between hypothyroid & B12d as both can be auto immune. I'm over 12 months in and still ed or eod, depending how I feel. I get 1 every 3 months from my GP.
You did a wise thing with the b12 injections. I took a high quality b12 from BSupps but it did nothing for me, zero, whilst others report having a good energy boost. Used an injection which worked quite well so some folks have very poor absorption with b12 as did I. Currently have an injection once a fortnight.
Hi Greygoose & Slow Dragon. I posted my bloods from September, but they seem to have disappeared! Shall I try and repost or did you see them?
Can you repost
Serum TSH level - 0.11 mU/L
Serum free T4 Level - 10.1 pmol/L
Serum free T3 Level - 4.6 pmol/L
Blood Test Results from September 2024
Didn't see any results, no.
Serum TSH level - 0.11 mU/L
Serum free T4 Level - 10.1 pmol/L
Serum free T3 Level - 4.6 pmol/L
Blood Test Results from September 2024
Thank you. But there aren't any ranges.
Blood Test Results From September 2024
Serum TSH level - 0.11 mU/L - 0.30 - 4.20 mU/L
Serum free T4 Level - 10.1 pmol/L - 9.00 - 19.00 pmol/L
Serum free T3 Level - 4.6 pmol/L - 3.00 - 5.40 pmol/L
So, what were you taking at that point? How much of each? Your FT4 is very low and that could be the problem. Some people just need a high FT4 even when their FT3 is good.
FT3: 4.6 pmol/l (Range 3 - 5.4) 66.67%
Your FT3 is quite a decent level but could be you need that higher, too. A lot of hypos need it about 75% through the range. And your TSH is still visible so could be that your pituitary also considers you levels are too low.
Blood test done through NHS. Blood test always done before taking any meds with water and before 9.00. T4 was 75mcg for many years until I found out that I wasn’t converting. On T4 = 62mcg and T3 5mcg x 3 times a day for approx 18 months. I can’t cope with more T3 as I get palpitations. 3 times a day for me is doable. 4 does is just too difficult to slot in. Perhaps I will experiment with more T4. Thank you for all your help. I am very grateful.
So, when that test was done you were taking 62 mcg T4 and 15 mcg T3, is that right?
Do you always take your T3 on an empty stomach and well away from other medication/supplements?
Why is T4 too difficult to slot in?
Yes you are right I take 15mcg of T3 over the day. 15mcg split into three doses. 8.30am 5mcg of T3 with 62mcg of T4. 3.00pm 5mcg T3 and the last dose of 5mcg of T3 9.00pm. I have a clear half an hour of no food only water ether side of taking T3. I have also read that you should have a least 6 hours free before taking your next T3 dose. I would be really struggling to get four doses in, bad enough getting three in. Yes all T3 taken on its own and well away from food and supplements.
Oh, I see! I misunderstood! 
But I do't think anybody would suggest you split your dose into four. That would be unreasonable. If you increase your T3, you increase one of you three existing doses, like taking 10 at 8.30, or something like that.
I have also read that you should have a least 6 hours free before taking your next T3 dose.
Oh, dear, you have been reading some peculiar things! There's no reason that I know of for leaving 6 hours between doses. You schedule your doses for when it's most convenient for you - try taking it all in one go of you like. There are no rules about that.
What dose levothyroxine and T3 were you taking before these test results?
Was test done early morning, ideally just before 9am, only drink water between waking and test and last dose levothyroxine 24 hours before test
T3 ….day before test split T3 as 2 or 3 smaller doses spread through the day, with last dose approximately 8-12 hours before test
Free T4 (fT4) 10 pmol/L (9 - 19)
Ft4 only 10.0% through range
Free T3 (fT3) 4.6 pmol/L (3 - 5.4)
Ft3 66.7% through range
Many, many members find they need BOTH Ft4 and Ft3 at least 60% through range
so you may need to increase your Levo dose to improve low Ft4
Then you might need to reduce T3 ……if Ft3 goes up too much after next test
Blood test done through NHS. Blood test always done before taking any meds with water and before 9.00. T4 was 75mcg for many years until I found out that I wasn’t converting. On T4 = 62mcg and T3 5mcg x 3 times a day for approx 18 months. I can’t cope with more T3 as I get palpitations. 3 times a day for me is doable. 4 does is just too difficult to slot in. Perhaps I will experiment with more T4. Thank you for all your help. I am very grateful.
Was last dose T3 around 8-9pm night before test
You look like you need more Levo
Possibly then might only need T3 twice a day
But only change one thing at a time
Suggest you increase Levo to 75mcg daily
Retest in 8-10 weeks
Thank you so much for your help. Best wishes Brigette
Come back with new post when you get test results 2-3 months after being on higher dose Levo
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