I note like many of you have said that unlike other illnesses when we have our bloods checked the level of t3 is checked . So it's a test of the level of the drug we take . Unlike say diabetes where someone takes insulin but gets sugar levels checked and ketone levels but not insulin levels.
My only comparison is when someone takes digoxin they can have a digoxin level test done . Now when this is done blood should only be taken in the window 18 hours post dose up to pre next dose. It's taken once a day .
So I ask why arent we given an optimum time that we should have our bloods taken at post dose . Surely at some time just after taking a dose we have a peak in our blood stream till its absorbed . Is it 3 hours post dose .
I have heard people say dont take your tablet for 24 hours . Does this give a much lower reading though than if you did take it . Just asking if anyone knows if it does . And by how much .
I want to experiment with a higher dose but not put my heart at risk . I am sleeping a lot . I have increased my activity levels over the last 3 months . I eat only about 1500 calories . A reduction in the last 3 months and I have lost no weight . This plan always works for me in losing weight . So I am thinking I am under medicated.
My tsh is optimum. My t3 levels top of range . My t4 about 3 to 10 .
Has anyone noticed they needed more t3 when their lifestyle became more active . I used to do nothing. Now I walk 3.5 miles 4 to 5 times a week . I work once a week or fortnight but that activity level hasn't changed . I am ill the day after work or if I do more than the walk .
Thankyou for your help .
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poppppy
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So I ask why arent we given an optimum time that we should have our bloods taken at post dose . Surely at some time just after taking a dose we have a peak in our blood stream till its absorbed . Is it 3 hours post dose .
Because doctors simply don't understand. The time T3 peaks in the blood is often quoted as 2-4 hours. You may find this study interesting:
I have heard people say dont take your tablet for 24 hours . Does this give a much lower reading though than if you did take it . Just asking if anyone knows if it does . And by how much .
It's last dose of levothyroxine that should be 24 hours before blood draw. For T3 it's 8-12 hours.
It doesn't give a much lower reading if you leave 8-12 hours, that time gap is supposed to give the normal circulating amount of T3.
My tsh is optimum. My t3 levels top of range . My t4 about 3 to 10 .
Without the result plus reference ranges, unfortunately that is pretty meaningless so nobody can comment.
Thank you so much for your answer . I will make sure it is 12 hours after my dose that I have my bloods done thank you . Thank you for the article . I will read tomorrow thank you
Poppppy If we are on T3 we need to have our FT3 (that is the T3 circulating in our blood) level checked. This is to help us monitor our levels and along with symptoms to guide us on our dosage. There may be health risks if your FT3 level goes over range.
There are optimum times to test after your dose. The optimum time depends on whether you wish to test your level at its peak or at its lowest. It you want to check it at its peak you would test 2- 4 hours after intake; if you want it at its lowest 8 - 12 hours after.
On here we tend to advise 8 hours after (levothyroxine is 24 hours after dose). This is because for most of the day the blood level of FT3 will not be at its peak and we want to ensure that we always have enough hormones to function. If we went on peak readings we would be likely to be undermedicated.
The jury is out on the health risks which is why I said May Be. The doctors mention health risks of osteoporosis and heart issues. However many of the studies done used hyper patients with low TSH but they make no mention of what their FT4 and FT3 levels were.
One of the studies on bone density found that it wasn't osteoporosis that hypers developed but that their bone tissue was replace quicker before it had time to fully develop.
Now whether these studies are applicable to hypo patients with suppressed TSH but FT4 and FT3 in normal ranges is open to debate.
Oh lala! Is it weird that I was much calmer with hyper?!
Now I feel like I’m on crack on levo and lio just made it worse! I sweat profusely, I’ve been tachycardic since the day I was put on levo. Ah it’s a mess.
What vitamin supplements are you currently taking?
How do you take your T3
As single or split dose?
Two or three split doses?
We need to regularly retest TSH, FT4 and FT3. Also EXTREMELY important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common with Hashimoto’s
Ask GP to test vitamin levels
Recommended on here that all thyroid blood tests should ideally be done as early as possible in morning and before eating or drinking anything other than water .
Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip, best not mentioned to GP or phlebotomist)
If/when also on T3, make sure to take last third or half of daily dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test
Is this how you do your tests?
Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins
Thankyou I usually have my tests at random times . When I see the consultant she says have your blood taken . I have said sometimes I am 3 hours post dose so wont it be at a peak . But she doesnt show any concern .
Thank you for suggesting without food or water . I will try that next time and make sure i haven't had a dose for 12hours . It will be interesting to see if my levels are lower .
Thank you for your help and all the links . Thank you .
She doesn't show concern because she doesn't understand it sadly. I've had plenty of those over the years. It's why I, like most on here, test privately so that I can control the time and conditions and I pretty much ignore any NHS tests unless I can get them into the right time slot.
I take 75-100mcg t3 only at bedtime, so my test is 8-12 hours after my bedtime dose. Result is usually around 3, as i take a large dose my endo wanted several tests done in one day to get a better picture:
1st test 2 hours after 75mcg t3 result 12
2nd test 4 hours result 10
3rd test 6 hours result 4
So i spend 4 hours a day over range but it drops quickly, splitting dose never worked for me. My endo also checks my SHBG every 6 months to check im not over medicated, mine averages 58 (70-90) Luckily my then endo was not afraid of t3 and understands how it works, so he was perfectly happy with my results.
Wow thankyou for this . This is really useful . I am shocked how much the timing of the blood test changed your result . I am inspired that i may be under medicated. And I could feel better than I do . I often have y blood test within 2 to 4 hours after my tablet . And my result is in range so after 6 hours I would probably be below range .
I wonder what your results where for the next 18hours . I am sure they plateaued out . But then could they have gone lower first . How kind of your endo to do these tests . How knowledgable as well .
What is shbg test . I will look it up . Didnt know there was another test to check whether you were medicated optimally.
So thank you you have taught me a lot . So grateful for you taking your time for me
Tbh my Endo wanted to make sure I wasn't cheating the blood test to get more t3 he is very aware how easy it is to cheat, so it was done under supervision. He is shocked I can sleep after taking 75mcg at bedtime, I never get that wide awake feeling.
The shbg (sex hormone binding gobulin) apparently if you take too much t3 over a period of time you get a high reading, he caught a friend out hers was 120 so he knew she was taking too much and halved her prescription.
If your still in range at peak then you are prob way down for most the day, so yes you may be able to increase. Good endos are hard to find, mine is retiring soon
Gosh your endo is amazing . I love mine just for the sheer fact she supports me being on liothyronine (I call it lio ).as I know this is very lucky situation to be in . Apart from letting me stay on it her interest ends .
I may ask about the shbg test but I think I am pushing it.
I dont get any wide awake feeling after my dose at any time . I also saw research that showed people with a normal functioning thyroid . That their blood levels of lio are the same all day and night . With actually a minuscule peak in the night about 4 a.m . So does it matter if you take it day or night then . I thought from that that twice a day would keep your levels at a steady state . But Because you still have the remnants of previous doses in your system for about 3 days or more then I dont think it matters . It is very complicated because just because there is a peak in your blood levels .it is not showing the levels in your tissues or cells . Where it counts is it ?
You are absolutely right, its cell saturation that counts, not how much is sloshing around in your blood and i think how we feel must be an indication of that. Sometimes i feel great, sometimes ok but just as often i feel rubbish (bone tired, no motivation, joint pain, weepy, fed up and joyless!) i feel i will never be fully in the game again.
The SHBG test will not give you any indications to help it just shows if you take too much or too little over a longer period. Its thought you keep increasing until symptoms are gone, i was at one point on 150mcg a day but felt no better than when on 75mcg so the extra seemed pointless if no benefit, i do add 25mcg on busier days. I go by the 'spoons theory' (worth googling) for every bit of extra energy i use one day, it takes it from another, i have to prioritise work, dogs, food shopping, self care, everything else like housework is low down on my list. I keep reading in the hope i will find the missing bit of the puzzle but in truth for me, this is probably 'as good as it gets'
Aww endomad I am so sorry you have to go through this shit . I empathised with so much that you said . The different days . I try to pick up on patterns , causes for the bad days but can drive u mad .
I did read the spoons analogy . Brilliant . I exert my self one day and suffer the next . So then I think pace yourself but then i still have a spate of bad days so i am inclined to just go for it on a good day now .
I am curious re the 25 extra on busier days . Do u think it's a bit like insulin where if your activity levels increase you need more . I have increased my activity gradually .didnt walk anywhere to walking 3 miles about 4 times a week . So I think I need a higher dose.
I hope you find more answers . Take care and may you have many more good days than bad
LOL yes iv tried pacing myself and it doesnt work, so i go at everything like a bull at the gate on the good days, i can do 4 days work in one day but im on sofa for 2 days after.
I do think the extra 25mcg on busy days helps (i take at 10am) but of course it could be placebo effect but i dont care, if i think it helps thats all that matters to me, however it only works 1 or 2 days a week as i am too tired on the other days.
On good days i swim, walk, garden and easily do 12-15,000 steps but on other days it will be 2,000. One thing me, my physio and my dr cant work out is that i do not build strength from regular activity, as an ex sports woman that is odd, there are days i can be active the others i have no strength at all. So its good that you have been able to build up and increase your activity.
I have accepted that my life is quieter, slower and less sociable than it was, i always say 'i am a million times better than i was but a million miles from who i was before they removed my thyroid' I am a positive person by nature so i do know that bad days are just that and i have many great days xxx
You sound so lovely and I admire your attitude . I am a bit of a moaner . I suffer from depression intermittently. No known cause on my first episodes in my teens . I didnt sweat ever on strenuous exercise and my periods were very irregular . . I wonder if my thyroid was struggling intermittently many years before . They say that it is happening long before you show major symptoms dont they .
I never had major problems like needing my thyroid removed like you . I feel ashamed when I hear people like you being so strong and positive . I am just ords disease .
Where do you hail from . I am from north west england
😬 your Endo sounds like a scumbag ‘to make sure I wasn’t cheating the blood test to get more T3’ WTAF?? This is the sort of arrogant, condescending, patronising treatment that most of us get 😩 where’s the autonomy? Sorry I’ve honed in on just this one sentence but it just screamed out at me because I think patients are still putting up with it. It’s like Stockholm syndrome, we’re so grateful for even a little bit of the right attention/proper treatment that we forget that they’ve been our captors all along 😩
Hahahaha I know bless him, he was a really good endo tbh he is retiring to teach as he got so fed up the hospital and CCG always on his back about prescribing T3, i had individual funding so the hospital got reimbursed, he would be hauled in and dragged over the coals for asking for more than just basic tests and being diligent, he said it was like working with his hands tied behind his back. I use to see him every 3 months for prescription because my GP wouldnt continue my thyroid care, what a waste of NHS money, plus I had to split 2 tablets twice a day in water and throw the rest away BONKERS i just used knife but it meant they gave me nearly double the tablets!!! money to burn when another CCG paying!
He was a bit misogynistic though, so i always took my husband hahahha he would ask my husband 'and how is endomad? any signs of over meds? activity levels, was i sleeping etc etc hubby would then ask me, i replied to hubby who told endo hahahahhaha mad but it worked. If endo said something i didnt like i would frown at hubby who then closed him down on it
A previous endo didnt like my attitude and got his manager in to both try and bully me, he forgot i said at begining of appt i said i would record appt as i had a habit of forgetting stuff!! brilliant should have seen their faces when that was played back to them at a complaint mediation!
It is senselessly exhausting and emotionally draining having to fight all the time and Im not sure sometimes if it is worth it, I had to have 2 comments taken off my notes about my being argumentative and confrontational I have always kept at least a years stash of T3 in case i hit a prescribing or supply issue, not trusting your dr is not a good place to be. I have now moved to France and had no problems over T3 and it is as cheap as chips here. I also have no problem getting hydrocortisone for my adrenals.
I know how important the NHS is to the UK but cant help feeling if everyone paid a bit more in national insurance and had a system like in France the service would be worth fighting for. I also pay a top up insurance for health, no waiting lists here, tests done right away, i just dont think the nhs is fit for purpose anymore, good drs get hounded and threatened back into line, there is a shocking culture of drug company interference/bribery, price gouging, poor training, even poorer management and i speak as someone who has many friends who are drs & consultants. Could you imagine the uproar if they started saying to type 2 diabetics they cant have insulin!! type 2 can be reversed by diet and exercise, my thyroid wont grow back but they can withdraw my t3 if they wanted to but diabetics can keep eating the cake and sugar laden cola and still have meds. Over in france if your dr doesnt perform you move and they dont get paid, UK drs get paid whether they perform or not. LOL rant over x
Oh dear lord! 😩😂 I have to laugh or I’d cry! The stories are just endless! It terrifies me that I have another 30/40yrs of trying to source T3. Re the NHS, it won’t matter how much more we pay in, it’s just getting used improperly. My mum was a civil servant. They ploughed in a milllion pounds plus (NI so small population) to get this hand held devices for SW and midwifes was ect to record patient info. Worked on it for a year and then decided that no it wasn’t fit for purpose 😩 she had many stories like this and it would make her so frustrated!
Have you optimised vit D, vitB12 , folate and ferritin to support conversion and thyroid function?
How much T3 are you taking?
Without full labs for TSH, FT4, FT3 and antibodies plus nutrient levels it is impossible for members to evaluate your thyroid status.
Do you have a copy of your diagnostic test results ie before starting medication?
This helps point to why you are hypo. You are entitled to request copies of any results in your medical notes.
Finding your optimal dose e on T3-only can be a case of trial and error, as is finding the dosing times that suits you best......because we are all different!
Listen to your body!
Taking T3 only will lower your FT4 and your TSH.
Test about 12 hours after last dose and on an empty stomach.
Medics are fixated on TSH results... and wrongly often ignore FT4 and FT3.
TSH is a pituitary hormone, not a thyroid hormone! It is important for diagnosis but not so much for monitoring.
I believe that taking T3 only is the last resort, I take it you must have titrated different T4/T3 combos before T3- only.
Do you wear a Fit-bit....this is useful for monitoring your basic heart rate to avoid
overmedication.....check on waking, and monitor heart rate during the day.
I take a high dose of T3 - dangerous unless, as I have, you have a form of thyroid hormone resistance - and I take it in a single dose at bedtime. Thyroid medication is not a quick fix....it took me over 2 years to get to the bottom of my problem!
I'm not a medic just another member who has had to look for the answers medics failed to find....with much help from well informed and experienced TUK members.
Thank you for this . Hi yes went on liothyronine because my t4 to t3 conversion was poor .
My tsh was brought into range with levothyroxine and my t4 was maximum in range it could be . But t3 tests on several occasions came back as under range at 3 . When range was 3.5 minimum. So experimented with gp with liothyronine. .
Now under endo . I removed thyroxine following Paul robinson protocol . Endo tried introducing levothyroxine back on 2 occasions but I became ill both times . I would love for it to have worked .
Sorry no history and results but I guess it was because I was mostly interested in peoples thoughts and advice on the correlation of times of venepuncture with levels
Thankyou for all your concern . Very kind of you . I had forgotten about the pulse checking . It has made me think . That I had noticed my pulse has slowed to 50 to 60 bpm . Used to be 80 for years pre diagnosis and up till last year or so . So another reason I amy be under medicated .
Because.... without the person having a form of thyroid hormone resistance far too much T3 would enter the tissues/cells where the T3 becomes active - a form of thyrotoxicosis would occur. This can be life threatening.....hence dangerous.
The T3 in the serum (blood) does not become active until it reaches the cells
Any excess T3 left in the serum that has not overcome the resistance - and consequently has not reached the cells/tissues - will eventually be metabolised and excreted via the bowel and bladder.
It's essential that T3 - in a constant and adequate supply - reaches the cells via receptors so that it can get to work in the body to maintain good health
You said the T3 that has not reached the cells will be metabolized by the liver and excreted. What about the T3 that does reach the cells? That never comes back out? Lol
Thanks for the link DippyD, i found it very informative on many aspects of thyroid hormone action from heart to pregnancy, hyper and hypo symptoms and the reasons behind them, ( although it's been a while since i had to look up so many words in the dictionary)
Nice use of the word 'Hashitoxicosis' to describe a 'hyper swing'
However, trotting out the fixed 80% T4 / 20% T3 ratio for thyroidal hormone production as fact (without a reference) is disappointing, since,having looked at the Pilo study that this % is usually taken from, i now realise it's incorrect for many more of us than it is correct for.
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