Who else takes combo T4/T3 just once a day?
I’ve recently had another blood test done these are the results .
150 Levo 15mcgs T3
Last dose 24hrs previous day
TSH <0.3 (0.35-4.94)
Ft4 16.8 (9-19)
Ft3 4.52 (2.6-5.7)
I take T4 and T3 once a day in the morning. There’s a 24hr gap from last dose to test
The time gap of 24 hours was correct for Levo but for T3 you should have split your dose the day before the test into 2 or 3 and should have taken tbe last part 8-12 hours before the test. By leaving 24 hours you have a false low FT3 result .
How do you feel ?
I take Levo plus T3 and take them once a day except when testing and then I split my T3 into 2 doses the day before.
I can’t leave 8-12 hrs as if I take it past 1.30 I can’t get to sleep .
I was told a long while ago to add 20%?to the result if there’s a 24hr gap
The 20% is a guesstimate, there's no way of knowing it's accurate for an individual unless they've tested with the advised time gap and compared results.
The 20% ia a 'guessimate' based upon what was available then and if you read older posts on this forum you will see that was the suggested. However, the available calculation has since been abandoned as there are too many variables.
what does that mean ? The 20% has been abandoned?
Why is it a false low? If somebody doses only once a day then their ft3 will really be that low every day at that time under normal circumstances. What has been measured is the lowest that the ft3 gets on a once daily dose.
I suppose it all depends what you want to know... the highest perhaps for your own knowledge..... the lowest if the results are for Endo 😏
I want to know if I need a dose increase? I don’t have an Endo
I would think not with a reading like this 24 hours after T3... how is your heart rate, BP and temperature? They are a good guide
Why not just test 8-12 hours after dose as suggested to find your mid range?
well how do you feel?
As evidenced by the replies here, there is so much debate about the best time to test for an ‘accurate’ reflection. Taking bloods is just one of many ways to evaluate if you need a dose increase and helps provide different pieces of the puzzle. What is your temperature like? What are your current symptoms? What is your HR like?
I would not adjust my dosage based simply on the bloods, you could have excellent bloods and still feel poorly. I think the over reliance on bloods these days is detrimental to getting well in many cases. There are too many variables and once you add T3, getting an accurate reflection of what is going on at a cellular level is even trickier.
Weight gain. Constipation . Thinned hair.
These could be to do with my age ? 70
Have you had your Vitamin B 12 , Folates , Vitamin D and Iron/Ferritin tested in the last six months ?Yes, these could be age , but also low B12 or Folates , or Vitamin B 12 or Folate deficiency are often more common in older people but seldom regularly tested for.
These issues can effect your thyroid function and how well you absorb your thyroid medication, other drugs , supplements and nutrients from food too .
They cause a lot of issues in themselves including Fatigue , Insomnia , Palpitations, Dizziness , Muscle weakness and problems with digestion , skin and hair.
It's worth requesting for these blood tests to be done as regularly as you are allowed , especially if you have thyroid issues , and collect the results just as you do for your thyroid panel , as if they are borderline low they will tell you it's normal , but what is normal in the range may not be normal for you and you may need to start B12 and Folate supplements, and extra Vitamin D to prevent them getting worse or to improve your overall symptoms.
If total B 12 results keep showing as normal but your symptoms are not improving you need to request an Active B12 test to make sure that proper B12 conversion is occurring.
I had very rapid weight gain in strange places , the muscles were weak and reducing in size on my arms and legs and my skin and hair were awful.
I had both Vitamin B12 deficiency anaemia and Vitamin D deficiency. Since starting injections for B 12 , and increasing folate and vitamin D supplements I've been able to control my symptoms better. I think it's worth ruling out anything else going on before changing the dose just in case there is a missing piece in the jigsaw that a thyroid drug modification alone won't change as much. Hope that is useful. Take care , Bee
yes I have all of these tested every 12 weeks by my haematologist. They are all optimal and I’m very careful to keep them that way . Have done this since 2014
That makes sense that it’s the lowest it will be if taken once a day. So theoretically it’s actually higher through the day than the results show? Perhaps that’s why I don’t feel the need to dose throughout the day!
Do you think the results are ok? Only asking as I have put weight on over last couple of years and my constipation is quite bad so need to take a laxative at night
Yes both ft4 and ft3 are at their lowest. So for most of the day your levels are higher. If you tested 2 to 4 hours after your doses then you would get ft4 and ft3 around their highest.
If you tested ft4 and ft3 around 12 hours after doses you'd get an average level .
If those were my results and I wanted to see if I could improve lingering symptoms I might consider testing after 12 hours to get an idea of average levels to see what leeway I had to change doses.
Or based on the lowest results I might consider reducing my levo slightly by 12.5 per day maybe and once levels had dropped, adding in another 5mcg t3. This would be to see if that different balance between t4 and t3 improved the lingering symptoms.
On combo it is trial and error as to the doses we need. When we are reasonably well we don't want to make big changes to spoil what we already have.
I would also add that after 18months on steady levo t3 doses I am still finding that symptoms are improving with no changes to my dose so it can be a very long term thing
thank you for your reply Lalatoot .
I can’t test 12 hrs after taking my morning doses as that would be 8pm and Drs are closed then.
So I really don’t know what to do!!!
I increased T4 about 6 months ago from 125 to 150 but kept the t3 the same dose. The results showed that both ft4 and ft3 had increased .
These were the results when on the lower t4 dose.
24/06/22 125mcgs Levo plus 15mcgs T3 test 8.25am last dose 24hrs Tsh <0.03(0.35-4.94)Ft4 12.5(9-19)35%Ft3 3.7(2.6-5.7)35.48%Add 20% 4.44 58.6%
"I can’t test 12 hrs after taking my morning doses as that would be 8pm and Drs are closed then."
8 -12 hrs is good enough for T3 , it doesn't have to be 12hrs .
(8 -12hrs is far enough away from the dose of T3/ T4 to miss the 'high peak' that happens when it is all absorbed into the blood all at once .. this high peak lasts from aprox 2 hrs after taking T4/T3 ~ to aprox 4-6hrs after taking them) .
So eg. you could take T3 at 7 /8am and test at 3 /4pm . This would show your mid/ average levels for that T3 dose pretty well ... however it's important to note that it would not show TSH at it's highest.. in late afternoon TSH would still be pretty close to it's lowest ... TSH is lowest between aprox 1-3pm each day ,then rises again to it's highest around midnight-2 am (aprox).
If the results are going to be seen by a GP you really don't want' to be showing a GP a lower TSH .. or else it is highly likely they will want to reduce your dose.... however in your case your TSH is already lower than they can measure.. their test machine can't measure anything less than 0.03 (hence the <) .. so if they are OK prescribing with your supressed TSH , it may not matter in this instance .
If results are 'just for you' , and you're not interested in getting the highest TSH, you can test at whatever time of day you want ... eg. you could get a private fingerprick test and test at 8 pm if you prefer.
Note ~ if you test Levo after 8 -12 hrs and you usually test after 24 , the result you get for fT4 will be slightly higher than you would usually get... but 8-12 hrs is still long enough to miss the high peak that happens between aprox 2-6 hrs after taking Levo .
These graphs show the effect of fT4 / fT3 levels at various time post dose .
Top Graph ~ Top Line shows fT3 level. (in people taking T3 + Levo)
Middle graph ~ Bottom Line shows fT4 level (in people taking T3 + Levo)
so basically ft3 is only high for a short time after it peaks then drops for the rest of the day? So it’s not running high all day?
I don’t ever feel it kick in or feel it dropping.
Is a finger prick test comparable to a venous blood test ? Asking as my friend is a phlebotomist and says they differ
What time the FT3 level is high in the blood is not an indication of what time it get's into your cells... it doesn't do anything in the blood .. it just goes round .. it only 'does something' once it gets inside a cell , once inside a cell, it makes that cell do 'whatever that cell does'.. (heart, brain etc )... the 'action' of T3 on that cell can last anything up to about 2 or even 3 days,( depending on all sorts of complexities)
So you can't look a those graphs as showing 'when you feel it '... they simply show when the level s are highest/ lowest as they are being carried around in the blood .
As for fingerprick vs venous ?.... it is not so much that which makes for all the variability we see in FT4 / fT3/TSH testing (although it may obviously have some impact .,,and some unforseen cock up's resulting in failed tests eg delay in sample arriving at the lab due to sitting in a hot post box during a strike in june etc.. or damaging the blood cells as they come out by squeezing the finger etc etc )
there are just as many differences in NHS venous tests when the samples are tested at different NHS labs , due to them all using different test platforms( machine) which use diff anaysis methods , made by diff manufacturers , and having diff [ref ranges] . The whole fT4 / fT3 / TSH system has a large ( and unacceptable) level of variation in results , but it's the best we've got at the moment (until the endocrinology profession pull their finger out and demand better/ closer comparability between diff test platforms/ labs ) .
So to get the best possible comparison between our own tests, we not only need to keep the variables of 'time of last dose' and 'time of day' under control ... we also need to use the same lab as far as possible.
I’ve been doing private finger prick tests on same day as NHS tests for a while. The ranges are different so they’re never the same result, but there’s a lot of similarity. Eg. If T3 is above range on one it usually is on the other.
I guess you need to work out what percentage each test is through the range, rather than look at the figure itself? Then compare percentages?.
I’m not really interested in that degree of accuracy as I adjust according to how I feel. Just need an occasional check.
Yes I agree with you Lala- it makes logical sense that if the take your dose at the same time once per day in the morning then the blood draw the following morning- if done consistently around the same time- will yield a consistent result of it being at lowest.
I take my NDT at 5.30 am and 11 am and don’t adjust It the day before a test. I consistently do/have tests done at 9 am which is 22 hrs after I take the second dose. I have no problems doing it this way. For me my blood work is a guide not gospel- and my dose in accordance with the alleviation of symptoms..
someone has just replied to me saying my ft3 after 25th is 62% so it high considering there was a 24hr gap!
So this has now really worried me Lalatoot
Don't worry. You just need to be logical and methodical and think about what you want to try. On combo it is all trial and error to see what suits.You can keep things as they are with your lowest ft4 at 78% and your lowest ft3 at 61%.
You could test at 4pm as tatty suggests to try to get more of an average idea of levels to see if that helps guide you
You could alter your current doses based on the results we have been discussing. As you don't want your lowest levels any higher I would suggest that your first step would be a reduction in levo dose. Wait 8 weeks then do bloods. See what your levels are and how you are symptom wise and decide what to do next.
It is not easy to decide what to do. It took me 2 years of slow methodical dose changes 1 thing at a time and then waiting 8 weeks and doing blood tests, till I found doses I wanted to stay on longer term.
I measure ft4 at its lowest and ft3 at its average level. My ft4 low is 50% and my ft3 average is 72%.
thank you Lalatoot
I ncreased my Levo to 150 as both ft4 and ft3 were on the low side after I started HRT.
These were my results after starting HRT so I decided to increase T4 and keep t3 the same.
As you can see , both ft4 and ft3 have increased since the increase
I’m going to need to do this soon but am on a tiny 5mcg dose of T3 and it’s a capsule. I already split T4 50 at night 75 morning.
Should I empty the capsule out and cut it with a credit card like a drug dealer….? Create myself 2 ‘lines’. 🤣 ( you can tell I’ve been thinking this through) I need the results to show low really, I have felt fab on it and it’s really settling nicely so I don’t want to change down or up.
Regenallotment I’m really happy to read you’re on T3. I remember you posting about long term depression/anxiety and suspecting a low T3 to be involved there. May I ask how you’re doing on it? X
this reply is nothing to do with me or my post.
Please post separately or DM the person
Should you ever wish to discuss or celebrate the success of someone else on one of my posts, please feel free 😉
So from my point of view, my question is to do with your post, I share your experience and take my meds similarly to you, I have the same question. So by contributing and adding to the responses, I have helped push your message up the reading list of the forum, enabling you to get more responses, I find reading other’s responses helps us all learn. I apologise you feel this post is hijacked and will be careful in my responses in future.
Socialite or gangsters moll hmmm 🤔 or watching too many dodgy movies 😏
If you want it to read low then leave a good gap and split the capsule, you can just mix half with water... though snorting might be hilarious so be sure to film it for us 🤣
Plenty of air in the capsules and see through so quite easy to judge your split and put the cap back together 🤗
You can never have too low a reading for an Endo 🙄
this is not a reply to my question . My post has been hijacked
Feel free to ignore responses to others
your reply isn’t answering my post . Perhaps create your own postv
There is a complication if you take combination T4/T3 like NDT. If you do the test 24 hours ahead the T3 will be low, but if you do 12 hours ahead the T4 will be high and TSH too low. I tend to opt for 24 hours and acknowledge the T3 will be low, mainly so the GP doesn’t panic and I don’t have to get into a huge debate with them about why I don’t need to reduce my dose based on artificially high T4 and low TSH (if that makes sense…….)
TSH is not affected by 'time of last dose'.
And fT4 is 'not much affected' by the time you get past 8-12 hrs... it is most affected between 2-6hrs post dose .
See the graphs i posted in other reply on this post Buttercups ~they are showing levels on T3+Levo combo rather than NDT , so not direct comparison, but .. TSH is not affected by time of last dose because that level has already been set by the levels of T4/T3 during the previous few days /weeks . TSH doesn't change on a day to day basis as a result of time of dose , but it does change each day as a result of 'time of test' due to the circadian rhythm for TSH . higher middle of night ~ lowest mid afternoon
do you normally dose once a day like I do?
yes. I normally take it when I wake during the night (somewhere between 2-4am) so I can guarantee an empty stomach………😉
how long after you take your doses is your blood test?
I would take that day’s dose after testing so about 28 hours (a bit naughty really….)
what do your results look like after that gap?
Thanks for your replies - much appreciated
my TSH has been slightly suppressed. My T4 low (just now scrapped into bottom of range, was below) and my T3 is low. Hence why I don’t want to risk arguments about lowering dose as I have already had comments about needing to lower dose to get TSH in range, even with a T4 of 9 (reference range 12-22!!)
yes I understand what you mean
how long after last doses do you test??
these are my latest results leaving an 11hr gap from last dose of t4 abd t3
13/3/23 Monitor My Health 150mcs Levo plus 15mcgs T3Tested at 7pm 11 hrs after doseTsh <0.01 (0.27-4.2)Ft4 20.1 (12-22)Ft3 5.8 (3.1-6.8)
interesting. There are people on here much more experienced than me, but I’m wondering if you take them separately whether the best timings to test are 12 hours after T3 and 24 hours after T4. I wonder if that might raise your TSH and lower your T4……
As I say I’m not an expert and am only speculating if it would give a different perspective of your levels…..
when I’ve put my results here before after leaving a gap of 24hrs I was asked to test t3 after 12 hrs which is why these results are like this as the purpose was to see what T3 was like.
After 24hrs my ft4 is always around 14.1
5/9/22 150 Levo plus 15mcgs T3 last dose 8.20 previous day TSH <0.03 (0.35-4.94)Ft4 14.1 (9-19) 51%Ft3 4.3(2.6-5.7) 54.94%Add 20% = 5.16 82.58%100 Estradot patch 24211/11/22150 Levo 15mcgs T3Last dose 24hrs previous day Tsh <0.03 (0.35-4.94)Ft4 14.1 (9-19) 51%Ft3 4.3 (2.6-5.7) 54.94.%
That makes sense. It’s complicated isn’t it when you are trying to balance both the results 🤦♀️
Amazing the difference in T4
well I did what I was asked and tested for ft3 after 11 hrs just to see what it was instead of 24hrs