Hi all, today I have received a letter confirming the results of a nhs t3 test i had 10 days ago, it basically says my t4 was 14.8 and my t3 is 3.7 (it says this is slightly lower than the normal range which is 3.9 - 6.8 ) and that this would suggest i need more levo and should increase from 100mcg to 100mcg alternating every day with 125mcg and in 3mths they want me to go back to see if there is an improvement. is this likely to improve my t3 / help me with fatigue/ brain fog?
thank you Ian
Hi Lora yes it’s come down slightly though (from 582 to 520 ) in past 8 weeks possible due to stopping drinking and magnesium supplements
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)
Is this how you did this test?
What’s the range on Ft4 ?
You may be able to tolerate 125mcg every day
What are vitamin D, folate, B12 and ferritin levels ?
What vitamin supplements are you currently taking ?
Seeing previous posts you also taking T3
If taking combination of levothyroxine and T3 you can’t tell how well you convert
Was this result from before starting on T3?
Hi I stopped taking t3 around 4 days before the appointment . I take magnesium and vitamin d and ferritin down a bit in last 8 weeks from 580 to 520 probably due to starting magnesium and stopping alcohol
It’s completely pointless testing unless continue taking both levothyroxine and T3 as normal (unless trying to confuse endocrinologist)
Your Ft3 is inevitably low if you stopped T3 4 days before test....it means nothing
Bloods should be retested 6-8 weeks after being on constant unchanging dose
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 5mcg dose 8-12 hours prior to test, even if this means adjusting time or splitting of dose day before test
Have you considered giving blood to lower ferritin....perhaps discuss with GP?
I was waiting to get the t3 results before seeing my doctor again about options for the ferritin issue. I thought stopping for the 4 days it would mainly be out of my system and souls show to the doctor I had low levels, Please forgive my ignorance but what effect does taking t3 having on my t3 levels? I started taking t3 as felt terrible and at first it really did make me feel better for a couple of months.
any dose change up or down takes 6-8 weeks to have effect
When taking any dose of T3 this is highly likely/inevitable that TSH goes extremely low/suppressed
When you stop taking T3 ......the Ft3 rapidly drops
But because TSH is low ....your own thyroid doesn’t make any hormones and any Levo isn’t rapidly available either ....it takes 5-7 days for levothyroxine to respond to a dramatic change in T3
Also suddenly stopping T3 will affect cortisol, gut function and then vitamin levels too
So if you stop T3 4 days before test....TSH will be low and so will Ft4 and Ft3 .....but Ft4 and Ft3 are false lows
It’s fine to take T3.....but if you want to test true levels you need to do it correctly....otherwise it’s giving false results that are impossible to read
Suggest you let levels settle and take levothyroxine and T3 at unchanging dose you were already on for 6 weeks
Then retest .....doing correct timing
Thanks, in my ignorance if I carried on taking t3 right up to the test It would
Look like I had no issues converting and have no chance of being prescribed t3. That was my “logic”
Well yes......if you’re trying to trick them into increase in dose
But there’s no point asking an opinion on here about false test results
No I didn’t want to give a false reading... I just wanted to ensure I didn’t make it look like I didn’t need to take t3 as my feeling is I do but ultimately I wouldn’t want to take medication I didn’t need incase of causing long term damage.
125mcg levothyroxine isn’t a high dose ...especially being male
How much T3 are you taking? 25mcg ?
As split divided dose? Or single dose
To know if you need dose increase....get bloods retested 6 weeks after once settled back on your current regime
I take 25mcg upon wakening and 12.5 at 1pm
So the day before test....suggest you take 12.5mcg waking. 12.5mcg 1-3pm and 12.5mcg about 9pm
Last levothyroxine in the morning, 24 hours before
Blood test 9am latest following morning
Although T3 has a short half life it would take more than 4 days for it to fully leave your system. There would still be a trace left.
T3 also affects TSH and Ft4. T3 tends to suppress TSH and lower FT4. Once you stop T3 or change the dose it takes weeks for TSH and FT4 to reconfigure at their new levels. This is why bloods are recommended no sooner than 6 weeks after a dose change
.
Your lowish Ft4 on your latest results may be due to the T3 you have been taking. You may still need an increase in levo but you cannot rely on those blood results for guidance.
If you want to find out if you have a conversion issue you need to stick to levo only for at least 6 - 8 weeks and then get TSH, F4 and FT3 done and look at the results.
I can understand the feeling better when you first started T3 - I did. But once the body has got used to it your dose needs to be adjusted to suit you. If you are on a combo of levo and T3 both levo and T3 doses need to be adjusted to get the balance that suits you. You have to adjust one thing at a time and then wait 6 weeks for bloods. This is where I am at the moment.
No I haven’t tried it, I don’t now where to get it from or the cost involved
Thank you for taking the time to do that
T3 results
update from endocrinologist 
How much T3 is too much?
T4+T3 combo
T3 trial from NHS endocrinologist 
