The aim of levothyroxine is to increase the dose slowly upwards in 25mcg steps until TSH is always below 2
Most important results are Ft3 followed by Ft4
When adequately treated most people will have Ft3 at least 50-60% through range. On just levothyroxine (which is Ft4) usually Ft4 will be a little higher at perhaps 70-80% though range
So your GP is correct you need dose increase in levothyroxine
What’s the range on Ft4 result
Retest thyroid levels 6-8 weeks after any dose change or brand change in levothyroxine
ALWAYS test thyroid levels early morning, ideally just before 9am and last dose levothyroxine 24 hours before test
Have you had coeliac blood test done
Or are you already on gluten free diet or dairy free diet
ESSENTIAL to test vitamin D, folate, ferritin and B12 at least annually
Would you wear a pair of shoes size 3 if your feet were a size 8? Both are normal sizes.Would you be well with an ft4 of 14.6 if your body was better suited to an ft4 of 19? Both are within the normal range.
The range is a spread of numbers where normal levels are generally placed. We each need to find where in that range our personal normal, our optimal, result is.
Your tsh suggests that your body is needing hormone levels higher than yours currently are. That for you 14.6 is not normal and that you need ft4 higher in range.
You can understand my confusion if so called “ normal” ranges are not necessarily “ normal” for individuals and are interpreted differently by different docs?🧐
IDK that different labs have slightly different ranges as to what FT4 should be but!?
Because your TSH is still high your doctor rightly wants to raise dose, but your symptoms and your thyroid hormone levels are more relevant than TSH (an indirect measure).
As SlowDragon and Lalatoot say your TSH is out of range and your FT4, though just scraping in at the bottom of the range is low. You must focus on how you feel not just what the lab work says.
I put something similar on another post - hopefully this may give some insight.
By all means use tests as a (rough) guide, but symptoms are unequivocally the best calibration to our individual wellness.
When an instrument is calibrated that is to ensure it produces consistent results that can be compared to each other. It doesn’t mean calibration to the individual should be ignored. We all respond differently to hormone replacement. I have a suppressed TSH - I accept this is required in my case to become symptom free. Treating the patient not the lab work.
Being under medicated to satisfy a ridiculous (and very unscientific) obsession with TSH leaves thousands with lingering symptoms that have short and long term serious health impacts in their own right. The most helpful measures are those of ACTUAL thyroid hormones. Not something made in the pituitary (TSH).
There will never be a test that accurately predicts the dose of replacement hormones each individual person requires. The test has to be calibrated to the person. A doctor should be noting an individual’s response to treatment and comparing the test results, thus treating the patient.
Sadly there is mainly a dosing according to the test results and ignoring symptoms, or putting it down to something the patient is, or is not doing ie gaslighting and doggedly treating the lab work (not the patient).
If the interpretation of tests and the inherent limitations are not properly explained to doctors and endocrinologists alike we will see no improvement in treatment.
Currently we have the ‘Your Normal’ (when in range) paradigm for blood test results. To give you a feel for how inadequate this method of ‘interpretation’ is :
I was ‘Normal’ at 75ug of Levothyroxine- though severely symptomatic. My 6 1/2 stone friend is fine on 75ug.
I was ‘Normal’ at 100ug - but still symptomatic.
I was ‘Normal’ at 125 ug - but still symptomatic
I became well at 150 ug of Levothyroxine and at 5’ 8” tall and just over 15 stone that may not come as a surprise, but I had to FIGHT for every dose increase.
In every case my FT4 was in range, but just in a different part. In NICE guidelines there is a dosing guide for levothyroxine mono therapy of 1.6ug per Kg. The guidelines have latitude in them, but most doctors don’t know enough to use it.
Improving testing for the most part will make no difference if the 🤡 reading off the lab sheets don’t know $*ite from pudding.
This is a systemic problem with actually a NOT so massive knowledge gap that needs plugging. The problem is, it is a WIDESPREAD knowledge gap. Science and medicine have long since parted company and basic scientific principles have been lost. New methodology has been introduced and doctors have not been trained to understand it. Even putting ‘normal’ on a lab test printout is abhorrent - it goes to reinforce the current paradigm.
My GP won't explain why I have hypothyroidism. He says basically we just treat it. I had to push every blood test for an increase in levothyroxine. Just had the worst bout of constipation I've ever had and only just had my levothyroxine increased from 75 to 100. I would take an increase any day. Go by how you feel. That's my advice. Hope you get well soon .
It’s generally accepted that TSH regulates/controls thyroid production of T4/T3 but my T4 level is normal at 14.60pm but why is my TSH raised.?
TSH (Thyroid Stimulating Hormone ) is a 'message' from the Hypothalamus/Pituitary to the Thyroid . (HPT axis)
Your High TSH is saying ....."the amount of T4 we have is not enough yet ".. so it asks the thyroid to make more . However your thyroid is a bit knackered , it can't manage to respond to that request well enough anymore (hence you being put on Levothyroxine)
Once someone with a knackered thyroid (that can't make enough T4) is taking T4 from Levo , then high TSH is not so much a message to their thyroid ...but rather a message to their GP asking them to increase the T4 by increasing the dose.
Your TSH can try asking your thyroid for "more T4 please' , and shout as loud as it likes ( high TSH is 'shouting') .... but your thyroid cant manage to make enough T4.
When your dose is 'enough' for you .. then your TSH will go down ( stop shouting)
just because 14 is 'in the normal range' that doesn't mean it's 'enough' for you
.. 14 is only enough for the person who usually has 14.
it is not enough for the person who usually has 20.
..... it's like shoe sizes .
size 5 is a 'normal' shoe size for women .... and so is size 7
.. the normal range for women's shoe sizes might go from [4 to 8]
But 'normal' size 5 shoes are no use to you if you have 'normal' size 7 feet. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
TSH 'asks' the thyroid to make more/ or less T4/T3 ( FEEDFORWARD) .
and TSH is also a reflection to how much T4/T3 there is in the blood and how satisfied the hypothalamus / pituitary are with that level ( FEEDBACK)
BUT... that is how the system works when the thyroid is making all the T4( and a variable amount of ready made T3)
Unfortunately the Hypothalamus /Pituitary are a bit thick ~ they can't tell the difference between T4 from the thyroid..... and T4 from a tablet.
once we are taking 'enough' of the T4 we need from a tablet.. the TSH goes down again so the thyroid is effectively turned 'off' (or at least 'turned right down' ) and so the FeedForward part of this conversation is less use .... the knackered Thyroid has largely 'left the conversation' once we are taking a 'full' dose of T4
GP's still use the FeedBack part of the conversation as a monitor of how 'satisfied' the body is with the dose of T4 taken (and how much T3 is being made from it) .
However it is not 'foolproof' to use just the TSH FeedBack as a monitor for how satisfied the whole body is once we are taking T4 only .... because it ignores the fact that TSH is ONLY a reflection of how satisfied the Hypothalamus / Pituitary are ... some other parts of the body may not be so happy with this new balance of "more T4: less T3"....... and the TSH can't reflect how the rest of the body feels , it is ONLY in conversation with the Hypothalamus , Pituitary and Thyroid (HPT axis)
The Hypothalamus / Pituitary may be saying "that's enough T4 thanks" , or even "that's a bit too much T4"......... but the muscles, or heart, or liver, or brain etc may be saying "but I haven't got quite enough T3 any more "
I would be suspicious of those TSH results as likely caused by assay interference. If you haven't supplemented biotin before hand you would need to retest with another lab to be certain.
Of course this could also apply to the T4 levels but to a lesser extent I believe, and if you are symptomatic, an FT4 level of 14 (12.0 - 22.0 ) is only 20% through range so requiring a Levo dose raise anyway.
For full evaluation you also need FT3 testing but if you can't manage that, if this were me I would just go with it.
i agree with radd , the TSH of 18.6 IS suspiciously 'higher than you would expect' even if your levo dose is 'not high enough for you' yet.
I hadn't paid attention to how 'unexpectedly' high it was at 18 in my earlier waffle about how it works .
TSH results can sometimes suffer from interference (from a technical part of the testing process).. the way to rule that out if TSH level continues to be unexpectedly high, is for GP to order a comparison test from different lab that use a different testing method ( and to check the patient isn't taking biotin which is known to skew some results )
But since your fT4 of 14 is pretty low and since 75mcg is still quite a bit less than most of us need , i'd take the Levo increase first, and see what happens to TSH after 6 weeks .
needing a dose somewhere between 75mcg and 150mcg Levo is very common. Some need more than that , some less .
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