I had a blood test done yesterday after 7 weeks on a dose of 82.5mcg t4 and 7mcg t3. My results were as follows: 16.6 ft4 (10-20) and 4.9 ft3 (3.5-6.5).
I am somewhat confused and disapointed by this as my last blood test in december on 75mcg t4 and 6mcg t3 showed 16.1 ft4 (10-20) and 5.1 ft3 (3.5-6.5) so despite an increase (I am doing so slowly due to sensitive reactions) my ft3 has decreased! This is not the first time this has happened either - my levels fluctuate constantly - since august last year my ft3 has gone 4.8, 5.2, 4.7, 4.6, 5.1, 4.9 even with miniscule changes in doses. Even more confusing is nothing ever changes - I take it at the same time every day on the dot, eat exactly the same meals, do the same acitivties, always leave 8 hours before the blood test NOTHING changes! I have continual iron deficiency but my ferritin level didn't change at all since my december blood test so that doeesn't account for the drop this time either. I am very confused and frustrated by this as I am working hard at slowly raising to try and feel better but this is becoming disheartening especially as it is frequently uncomfortable trying to increase. As you can imagine with an ft3 that low im very symptomatic - including a very poor gut function which im sure isn't helping.
Does anyone know why this could be happening? Is there anything I can do or should ask my endo about at my appointment next week? I take supplements b12, vit d, ferritin but my ferritin will not budge no matter what I do - liver, pills, sublinguals nothing helps. Any insights would be hugely appreciated. Thank you!
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owl87
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Thank you! I was diagnosed with secondary but my endocrinologist also suspected hashimotos so I suppose that would add weight to that! I have been trying to improve ferritin for over a year now to no avail. The only time my ferritin has been normal was when I had a higher ft3 level so I’m almost inclined to believe it won’t go up until my ft3 level raises.
Suggest you look at adding 2nd 6mcg dose T3 roughly 10-12 hours after first dose
Retest thyroid levels in 6-8 weeks
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)
Day before test split T3 into 3 doses
6mcg at 7am, 3mcg at 2pm and 3mcg at 9pm
If/when also on T3, make sure to take last third of daily dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test
Hi slowdragon wondering if I could ask when you eat around doses? I’m planning on starting taking t3 3 or 4 times a day but I also need to eat 5 meals rather than 3 big ones due to blood sugar issues and slow digestion which makes squeezing t3 in the 2 hours after 1 hour before thyroid hormone eating rule.
Does this apply so strictly taking t3? I notice on my liothyronine prescription it says take 30mins before food. Do you avoid eating and could leaving it 2 hours after but 30 minutes before eating or instead something like taking it 1hour 45mins after and 45mins before eating work OK?
I agree with SlowDragon that you are still under dosed. If you were taking an NDT, it contains 36 T4 and 9 T3 so if you double that, the ratio is 72 to 18. Perhaps you should just raise T3. Your T4 result is commensurate to your dose it appears.Do you take both T4 and T3 eight hours before your blood draw and what time of day? T3 will deplete faster than T4.
That’s what I am thinking - my t4 doesn’t seem to be converting much right now and it’s the ft3 I need to go up! I do - as I have secondary my tsh is never tested so it’s always by Ft4 and ft3 so my endo likes to see how my levels actually are doing during the day. I am lucky in that he goes more by symptom relief and prefers to use bloods just as a general measure but agrees that my ft3 needs to be much higher than it is right now!
Folate and b12 were done a while ago - folate was slightly over range, b12 was around 1000 but I take a sublingual once a week and used to have b12 injections. Vitamin d was done a few weeks ago and was good around 90 thanks to my supplementing. I am thinking of switching b complex as I just found mine has folic acid in it? And yes my vit d supplement has k2 in it too 😊
I think the changes in your fT3 level are actually not very large at all.
With any lab test there is a small % of variation allowed in the accuracy of any test result. And also our fT4 f/fT3 levels do not stay constant through the day , the levels go up and down a little every half hour or so, this is do with the way the thyroid releases the hormones, it is pulsatile , not steady. So ,your differences between 4.6 and 5.2 are actually fairly insignificant when you take the above into account.
If your fT3 results were going from say, 3.5 to 6 and back again it would be more notable , but honestly 4.7/8/9/5/5.1 fT3 results would be perfectly possible even on the same day, and would not mean it was fluctuating in an odd way.
Also an increase from 75/82 Levo and 6mcg to 7mcg inT3 dose is so small that after you have taken into account the ability of the body to compensate for changes by altering TSH and the complex interaction between that and your own thyroid's production of T4/3 ,you would not necessarily expect to see much difference in fT3 levels from your latest increase.
If you then add the fact that Hashimoto's itself will mess with levels on occasion .... well basically , i wouldn't pay any attention at all to a variation between 4.6 and 5.2. as i'm pretty sure you that for example you could have retested an hour later on the same day you got 4.6 and then get 4.8/9 .
Or at least that the conclusion i've come to from looking at information on the technicalities of blood testing and tables of results taken at frequent intervals over a 24 hr period.
For example see this graph of fT3 levels taken every 20 mins :- It's not the best example, as it's from healthy people ...but it gives you an idea of what i mean about how measurements don't just differ between morning and night , but also go up/down every half hour.
Thank you this is very detailed and helpful! Also helps put things more in perspective! I hadn't considered levels could move about a bit but it makes sense. I will keep this in mind going forward!
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