I got a phone call from the hospital today informing me that my surgery for this Sat has to be cancelled due to my Free T3 being to high...they said it was 22.5!! Result dated 20th December. My Free T3 was only 4.3 in Octoberso I am confused as to why it has shot up.
I had a 25mcg increase in meds before that due to my FreeT3 being to low. I am taking 75mcg and 75mcg in the afternoon. I have Been told to half my dose and have bloods done again in 5 weeks time to see if my Free T3 is within range.
I'm scared now that I might have a heart attack
I can feel my heat racing at night when I'm in bed.
How could my Free T3 shoot up so high does anyone know or has experienced this.
I'm so frustrated that I've. missed my surgery,
I had surgery last August with none if these issues.....could the blood test result be incorrect?
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Leyla123
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presumably from looking at your previous posts you are taking T3 , not levo ?
if you had a dose increase of 25mcg T3 then that is quite a large increase in T3 dose all at once ... and 150mcg T3 is a very substantial dose ..... so that ( and the fact that you have a fast heart rate) seem to indicate that the fT3 result of 22.5 is likely to be correct.
how many hours before test did you take last dose of T3 on test where fT3 was 4. 3 ?
and how many hours before test did you take last dose of T3 on latest hospital test ?
That us a good question I took my thyroid medication on the day of the last test, I didn't know they were going to check my thyroid....so maybe that would skew the result.
When it was 4.3 FT3 I didn't take my medication on that day.
yes time of last dose affects fT3 result significantly . after you take a dose of T3 the fT3 level in the blood rises very sharply in the first hour or two , stays at it's peak until (about) 4 hrs from taking it , when it falls quite sharply again
you usually want to be testing to see the average level... unless you / endo want to see how high it gets at it's peak , in which case you'd test within the first 3/4 hrs.
8-12 hrs from last dose of T3 is a reasonably good time to test if you want to avoid the highest peak, and see the more average level you have each day.
if you test more than 12 hrs from last dose you'll be seeing a level that is lower than you ever have on any normal day where you normally take 2 doses.
so your 4.3 result was a false low . because you'd never be as low as 4.3 at any point on a normal day when taking 2 doses , because you would have already taken another dose by then , so there is no point testing like that , it doesn't tell you anything about what your usual levels of fT3 are on any normal day .
I see what you mean.However I have to gave another blood test in about 4 weeks time yo seexwhat my FT3 levels are then....if out of range my operation will not go ahead. My endo has told me to half my dose to 75 mcg which makes no sense as I've been on 100mcg before and my bloods were fine. It's only since the 25mcg increase making it 125mcg that my bloods were 22.5 FT3...I took my meds on the am of the bloods as I didn't know they were going to test my thyroid at the hospital for surgery. It's so frustrating.
Sorry, but it isn't very clear what dose you are actually taking 125, 150 or 175mcg?You obviously need a large dose to be symptom free. There are some of us on the forum who need large T3 doses but we tend to just take it as one, single dose. Have you ever tried this or do you become symptomatic or start feeling achy or weird body sensations if don't take your second dose?
If you haven't tried just single morning or night time dose then give it a go. If you feel ok after just taking the 75mcg in the morning, just carry on and see how you feel.
Ideally you should try to do a private blood test before your hospital test to see what your ft3 is like. You could split your dose into 3 the day before test, so if bloods were 9am, take last dose at 9pm.
I understand and know what it's like to have to take a large dose, most important thing for you now is to have your operation
thought you were taking 75 + 75 ie 150mcg . not 125 ? and just noticed further down in reply to DippyDame you said you took 175mcg on the day .... not sure if these are just typo's or if you are unclear how much you are actually taking.
as far as i'm aware they will always test thyroid bloods before surgery , it's a routine part of pre-op . anaesthetist needs to know thyroid state for safety.
Can I check—that’s 75mcg liothyronine twice a day? Cos that is undoubtedly a hefty dose of T3. Can’t say I’m surprised your FT3 is so high (it’s a wonder it’s not higher to be honest).
I assume you must have some gut absorption issues?
Try not to panic though. This is where it’s a good thing it’s T3–the half life of T3 is quite short so the effects should wear off relatively quickly.
Yes that's correct 75mcg x 2I was taking 75mcg am and 50mcg in the afternoon with no issues....had a 25mcg increase which has shot up My FT3....so having to decrease
The best way to work with T3 is in small increases or decreases of 5mcg or as close as possible. Its an active hormone so needs to be treated with respect.
Most people on T3 monotherapy require in the region of 60mcgs as a full replacement.
Hi Leyla123, how long did you leave off meds before having blood test ? You should be following the protocol of no thyroid meds for 24 hours before blood test and no biotin vitamins for 2 weeks before blood tests. Is this the protocol you followed ? 🤔
Two weeks is an excessive time to avoid all biotin in supplements - especially low dose products (e.g. less than about 300 micrograms). Such long gaps could leave people under-dosed on other substances - for example, other B vitamins if they take a B complex.
helvella - Biotin supplementation and testing
A short article about how and why biotin can affect blood tests. Includes information about how to avoid any problems and how much biotin some foods contain.
24 hrs since last dose is appropriate for Levothyroxine, but Leyla is taking T3 in 2 doses a day meaning 24hrs from last dose is too long to get any idea of the usual level of fT3 in the blood . in these circumstances testing should be no more than 8-12 hrs from last dose T3 due to the shorter half life of T3.
Presumably you are self medicating 150mcg T3-only.
Yes? No?
Most medics would run for the hills before prescribing that amount... due to lack of knowledge
150mcg is a fairly substantial dose unless you have a form of thyroid hormone resistance. Has this been established?
Who is advising you re the use of T3? There appears to be gaps in your knowledge.....or theirs!
There should be a 12 hour gap between testing and the last dose of T3.....anything different gives a false high or a false low
Increasing by 25mcg T3 is like putting high octane racing fuel in an old Mini.....trouble!!
I need 100mcg T3 daily to function because I have a form of Thyroid Hormone Resistance, my TSH and FT4 are very low. But, on supraphysiological doses of T3 we have to monitor the old way.....by symptoms. Medics don't always understand this and try using lab tests which confuse things
If you are experiencing a racing heart rate that symptom would suggest your dose is too high.
It's the amount of T3 that reaches the nuclei of the cells that counts...it has to attach to T3 receptors there, and become active ( Serum T3 is not yet active)
If the T3 dose is too high, the cellular T3 will be too high, and symptoms of overmedication will result. eg racing heart rate
But, the high FT3 may be high because your dose and test were too close togethe
So, I agree with tatty's questions and will be interested to see your reply
For a start you need to revise your testing regime because to date it has resulted in unreliable results....I'm surprised the medics involved didn't notice the discrepancy between your dose and the labs!
HelloNo I am not self medicating I have an endo eho us prescribing....I had an increase in meds because my FT3 was to low. I have been on 125mcg for a couple of years with no problem....the problem may be that I took my meds 175mcg on the day I had the bloods done at the hospital...I didn't know there would test my FT3. So maybe that's why the reading was do high. I do not convert T4 to T3. I think I may try and get another blood test without taking my meds to see where I am at.
not converting T4 to T3 very well certainly explains your need to take some T3 , but it doesn't explain why such a large dose is needed/tolerated.
most people taking T3 don't convert very well which is why they ended up taking it , but most of them would be extremely overmedicated on 150mcg . (usual dose for T3 only is around 60 /75mcg ish).
most of us would not consider a 25mcg increase in T3 to be gradual though , 5mcg adjustment up or down is gradual for T3 .
25mcg is gradual for levo increases, but 25 mcg T3 is a pretty large increase in dose , (verging on reckless to be honest ~especially if the dose is being increased on the basis of incorrect blood tests as yours seems to have been )
oh , i say that because you wrote in your post : " I had a 25mcg increase in meds before that due to my FreeT3 being to low" ..... you didn't mention TSH was high.
If you can give full details when asking for advice ie. results with ranges / date / dose for previous 6 wks / time of last dose before test , it helps avoid misunderstandings
If you body is depleted of certain vitamins Google yr symptoms and see which vitamins are low on most people don't have this checked and Drs don't check it either unless you bring it up check ur
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