I've posted before and had some really good advice so hoping someone can help me with my next conversation with my GP.
In September my GP called me in to discuss reducing my dose of levothyroxine from 175mcg daily to 150mcg daily because of my low TSH (see below). I wasn't feeling ill but she was concerned. In the end she agreed that I could take 175mcg / 150mcg on alternate days.
My latest blood results are below and I'm not sure if they have improved enough to stop her reducing my dosage again.
Also is the T4:T3 ratio ok?
Thanks for any advice you can give.
September 2024
TSH 0.02 mIU/L (0.3 - 4.2) -7.2%
Free T4 (fT4) 19.2 pmol/L (9 - 23) 72.9%
Free T3 (fT3) 5.4 pmol/L (2.4 - 6) 83.3%
T4:T3 Ratio 3.556
C-Reactive Protein (CRP) 4.9 mg/L (0 - 5) 98.0%
January 2025
TSH 0.04 mIU/L (0.3 - 4.2) -6.7%
Free T4 (fT4) 16.7 pmol/L (9 - 23) 55.0%
Free T3 (fT3) 4.2 pmol/L (2.4 - 6) 50.0%
T4:T3 Ratio 3.976
C-Reactive Protein (CRP) 4.9 mg/L (0 - 5) 98.0%
Written by
Moonwalker43
To view profiles and participate in discussions please or .
Hi , most GP's will think they should reduce dose further with TSH 0.04 ,
your fT4 and fT3 are both significantly lower though , so if you really don't want to reduce further at the moment , you could try using this :
( but obviously it all depends how you feel symptom wise, if you still feel ok , then it's worth trying a very slightly lower dose as the aim is to take the lowest dose we need to fee well , not the highest dose we can tolerate ....... and if you can feel well on a dose that keeps TSH just within range , you'll have a lot less hassle when you have any dealings with the medical profession )
.also , you can try and discuss the following concept with GP ( or use it to baffle them into submission ) Taking T4 causes a slight shift in TSH in relation to T4 levels , compared to people who get their T4 (and some T3) from their thyroid ~ patients on levo tend to have relatively higher fT4 / relatively lower fT3 / relatively lower TSH~ meaning 'low TSH' does not mean quite the same thing once someone is taking levo : healthunlocked.com/thyroidu.... tsh-is-just-the-opinion-of-your-pituitary-about-your-dose-but-your-pituitarys-opinion-is-a-bit-warped-once-you-take-thyroid-hormone.
Thank you Tattybogle. That’s really interesting and I’ll use the information as a reason to not just drop the dose without considering the impact if I need to when I see the GP.
What is the ideal T4 to T3 ratio or isn’t there one?
The problem is, that your TSH might not come into range again, even if you are reducing your levothyroxine right down - however, it will probably make you very unwell. Some people have a low or suppressed TSH even with small doses of levothyroxine.
How are you feeling at the moment? Do you feel the same than when you were on the higher dose or is there any difference? If you feel the same without any ill effects, that's great. However, most people need their levels a bit higher between 60 and 70% through the range.
I would definitely insist not to reduce any further down and if you are getting some symptoms, you may want to think about increasing your dose slightly again. You can argue with the GP that a general replacement dose is 1.6mcg per kg of weight (prescribing guidelines), so a person weighing 63kg would need around 100 mcg levothyroxine.
I think I probably feel ‘different’ for reducing the dose slightly as I recognise now that I was having some heart palpitations at night which I’m not now. However I’m now suffering from hot/cold and tiredness more.
I weigh 64.5kg and so am taking more levothyroxine than the 1.6mcg per kg
I don’t want to reduce my dose anymore as cutting down 25mcg every other day only increased my TSH by 0.02
I will definitely get my nutrient levels checked.
Juggling the dosage and levels is confusing so thank you for your help.
Well, the 1.6 mcg/kg is just a rough guide - much more important is how you feel and even more importantly, at what levels your T4 and T3 are. Your T4 and T3 in September looked okay, if you can tolerate slightly less without ill effect, that's great but you should not feel that you have to reduce your medication to fit any numbers. How you feel with it is more important. For me both hormones around 50% would be too low, even if that would fit better with the 1.6 mcg... some people may need even more than that (for example some people may have more absorption problems, so they may need a higher dose to build up a similar level than some people get with a lower dose).
Cold and tiredness are clear signs of hypothyroidism, so that is an indication of too low hormones. You may find your sweet spot by increasing slightly (maybe just take 150mcg on 2 days), but like you have mentioned, reducing further should not be an option, as those hypo symptoms will increase and your TSH will not change much as a result of it either.
Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.
Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.
) Taking T4 causes a slight shift in TSH in relation to T4 levels , compared to people who get their T4 (and some T3) from their thyroid ~ patients on levo tend to have relatively higher fT4 / relatively lower fT3 / relatively lower TSH~ meaning 'low TSH' does not mean quite the same thing once someone is taking levo : 
Medicheck Advanced Thyroid Test Results...your advice please
Latest blood test results 
Interesting results - Euthyroid
Latest results 
TSH results help
