I’m currently taking 200mg of Levothyroxine(been on this dose for 12 months) I have bloods done every 6 months but on my last bloods in may my GP has reduced my dose down to 75mg. I’m worried this is too much of a drop surely it should be done gradually or bloods should be repeated?? Has anyone had a similar experience?
Many thanks x
Mrsuns01
You are correct, normally dose reductions should be 25mcg, retest in 6-8 weeks.
What were your test results, with reference ranges, at the time this big reduction was made?
Do you have autoimmune thyroid disease aka Hashimoto's?
I’m really rubbish with my thyroid I’ve always just listened to my GP and did what he said, I’ve no idea if I have Hashimotos, I was diagnosed aged 21 I’m now 37, I have a family history on both sides, & my mum & auntie have celiacs aswell as under active thyroid. I did ask my GP my results from the latest blood tests & all they said was my TSH was 0.03 and my T4 was 26.1 I don’t know if they have tested for anything else. I have a phone appointment with my GP on Monday so I wanted to come on here & get a bit more info xx
Mrsuns01
You need to get hold of your results.
Never ask a doctor, they are never helpful, they'd rather we didn't understand.
Speak to the receptionist, ask for a print out of your results, here in the UK we are legally entitled to have them without question or charge.
A TSH of 0.03 is definitely below range, and FT4 of 26.1 is most likely over range. This would suggest possible overmedication but not to the extent that such a drastic dose reduction should be made. 25mcg would have been adequate followed by retesting in 6-8 weeks.
You also need to find out if your thyroid antibodies have ever been tested.
Thank you so much, after reading some of this forum can’t believe it’s taken me so long to look into all this. I’m going to speak to the receptionist Monday morning & hopefully I’ll have more info for when I speak to the GP, thank you I really appreciate your help x
You're not alone Mrs 
it took me 17 years to start looking . Still, better late than never !
Sounds highly likely cause is autoimmune thyroid disease (hashimoto’s) as there’s strong family link with autoimmune disease
For full Thyroid evaluation you need TSH, FT4 and FT3 plus both TPO and TG thyroid antibodies tested. Also EXTREMELY important to test vitamin D, folate, ferritin and B12
Low vitamin levels are extremely common, especially if you have autoimmune thyroid disease (Hashimoto's) diagnosed by raised Thyroid antibodies
Ask/Politely insist GP test vitamin levels
Only ever reduce levothyroxine by 25mcg maximum at any one time and wait minimum 6 weeks before retesting
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 do your tests?
Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins
List of private testing options
thyroiduk.org/getting-a-dia...
Medichecks Thyroid plus ultra vitamin
medichecks.com/products/thy...
Medichecks often have special offers, if order on Thursdays
Thriva Thyroid plus vitamins
Blue Horizon Thyroid Premium Gold includes vitamins
bluehorizonbloodtests.co.uk...
Do you feel over treated?
Many people when adequately treated have very lowTSH and high Ft4......only over treated if Ft3 is over range
Of course NHS won’t test Ft3
Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,
"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.
In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l.
Most patients will feel well in that circumstance.
But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.
This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."
You can obtain a copy of the articles from Thyroid UK email print it and highlight question 6 to show your doctor
please email Dionne at
tukadmin@thyroiduk.org
Are you sure he didn’t say 175 as that would be a drop of 25mcg
No I spoke to 2 receptionists & a doctor I stated several times I was on 200mg & surely a drop of 125 couldn’t be right?? But they were adamant that’s why I’ve asked for a call back from my actual GP who authorised the prescription.
Well, in that case I would refuse such a massive drop. How do you feel, that’s the most important thing. Have you had your FT3 tested because if your FT3 is still in range then you’re not over medicated. Tell your Dr that you want your FT3 tested before agreeing to a decrease. Whatever you do, don’t take a drop of 125, it will make you ill
Yes Mrsuns, i agree with Gingernut. Politely refuse to reduce your dose by that much until GP can show that you are over range on an FT3 test.
Don't get fobbed off with 'we cant get that done, the lab wont do it, i've never heard of it etc' - my NHS GP's have had 5 done over the years, when THEY wanted to. (i am on Levo only,same as you), It is called a Free T3 test, there is also a Total T3 (TT3), but you want FT3
I agree with SeasideSuzie, it is likely your FT4 of 26.1 is over range, (but that doesn't mean your FT3 will be) so you may need a reduction , but FT3 is really the most important test for seeing if your level is 'dangerous'.
If FT3 is not over range it is not immediately 'dangerous'.
There are longer term risks associated with TSH<0.03 which your GP may be worried by, but they are 'relative' and you should be sure you understand the pro's and cons fully before letting yourself be frightened into changing a dose you feel well on. (sadly it is unlikely your GP will have read the detail of these risks, and may be just reading the 'headlines') -you can find references for actual the research in this Forum, so you can make your own mind up on the 'risks' .
I have had a TSH of around 0.05 ish for 15 yrs, so have looked into plenty of research on the subject.
P.S
This is just my 'feeling' , but i think they might need your 'agreement' to reduce a dose of levo. And i also think they are currently being 'advised' that '100mcg is enough for most patients,test TSH once a year, job done .'
Thanks so much for the info I really appreciate it x
That’s what I said to them it will make me ill, I’m going to ask them to repeat my bloods & ask for my FT3 & see what that say x
Would agree absolutely with Gingernut44
Insist on full thyroid testing including Ft3 and vitamin D, folate, ferritin and B12
Plus coeliac blood test too
Meanwhile you could agree to 25mcg dose reduction
guidelines by weight might help
Even if we don’t start on full replacement dose, most people need to increase dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until on full replacement dose
NICE guidelines on full replacement dose
nice.org.uk/guidance/ng145/...
1.3.6
Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.
gp-update.co.uk/Latest-Upda...
BMJ also clear on dose required
bestpractice.bmj.com/topics...
If you have gluten intolerance or especially lactose intolerance this can mean you need higher dose levothyroxine than guidelines
Lactose intolerance is very common with Hashimoto's
ncbi.nlm.nih.gov/pubmed/240...
Lactose intolerance was diagnosed in 75.9 % of the patients with HT
read.qxmd.com/read/24796930...
These findings show that lactose intolerance significantly increased the need for oral T4 in hypothyroid patients.
Thank you so much I’m not going to agree to the dose, I really appreciate the info x
200 is a very large dose unless you are a very large dose unless you are a very large person.
He was probably quite worried about the lab results. Every time I have had adjustments in the 40 plus years I have taken that drug the adjustments were very small.
I have always been on around 175-225mg I wouldn’t consider myself a “very large” person at all I’m a UK 16 so would consider myself normal
Strongly suggests lactose intolerance then
If you weigh yourself in kilo x 1.6 = approx levothyroxine dose according to guidelines
If taking substantially more than dose by weight that suggests.....malabsorption....lactose intolerance..low vitamins...gluten intolerance....or a mix of all of them
Guidelines on dose by weight = 200mcg Levo = 125kilo = 19 stone 9lb
So if I work it out like that it should be around 125mg x
Didn’t even know it could be worked out bu weight x
Do you always get same brand of levothyroxine?
Always take levothyroxine on empty stomach and then nothing apart from water for at least an hour after
Likely poor converter of Ft4 to Ft3
Next step is to get full thyroid and vitamin testing
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)
Yes always have activis brand, always take it first thing & I don’t have anything to eat for at least 2-3 hours. I have never not taken my tablets though before my bloods I’ve always taken as normal. So I am going to push for a repeat blood test. x
So if you took levothyroxine before blood test you have falsely high Ft4
Likely to have Ft4 within range if retest correctly
GP will deny timing of test and last dose is important
Thyroid patients know otherwise
NHS England Liothyronine guidelines
Note that it says test should be in morning BEFORE taking Levo thyroxine
Also to test vitamin D, folate, B12 and ferritin
sps.nhs.uk/wp-content/uploa...
Dr Toft, past president of the British Thyroid Association and leading endocrinologist, states in Pulse Magazine,
"The appropriate dose of levothyroxine is that which restores euthyroidism and serum TSH to the lower part of the reference range - 0.2-0.5mU/l.
In this case, free thyroxine is likely to be in the upper part of its reference range or even slightly elevated – 18-22pmol/l.
Most patients will feel well in that circumstance.
But some need a higher dose of levothyroxine to suppress serum TSH and then the serum-free T4 concentration will be elevated at around 24-28pmol/l.
This 'exogenous subclinical hyperthyroidism' is not dangerous as long as serum T3 is unequivocally normal – that is, serum total around T3 1.7nmol/l (reference range 1.0-2.2nmol/l)."
You can obtain a copy of the articles from Thyroid UK email print it and highlight question 6 to show your doctor
please email Dionne at
tukadmin@thyroiduk.org
Mrsuns01
Although the guidance says
1.36 Consider starting levothyroxine at a dosage of 1.6 micrograms per kilogram of body weight per day (rounded to the nearest 25 micrograms) for adults under 65 with primary hypothyroidism and no history of cardiovascular disease.
It clearly says that is the starting dose and then it goes on to say
1.4 Follow-up and monitoring of primary hypothyroidism
1.41 Aim to maintain TSH levels within the reference range when treating primary hypothyroidism with levothyroxine. If symptoms persist, consider adjusting the dose of levothyroxine further to achieve optimal wellbeing, but avoid using doses that cause TSH suppression or thyrotoxicosis.
So the dosing by weight is not mandatory, it clearly states that further adjustment of dose should be used to achieve optimal wellbeing, and there is no guidance or limit on what that should be. We need what we need, we're all individual with individual needs. I expect there are hundreds of members here whose dose does not coincide with the 1.6mcg per kg of body weight.
Years ago I was stable on 150mcg Levo. If we work out 1.6mcg per kg of body weight, that would mean my weight would have been 93.75kg or 14st 10.7lb. I have never in my life been that weight, my weight has always been between 10 stone to 11 stone.
10 stone is 63.5kg which would mean 101.6mcg Levo. I was never on 100mcg Levo except when titrating up to my optimal dose.
Wholeheartedly agree,
And if you actually use what they say, that is - rounded, the dose per kilogram varies hugely. Between about 1.38 and 1.76 micrograms per kilogram. An awful lot is effectively hidden by using that one word - a variation of over 20%.
Weight - weight in kilograms
Calculated dose - dose using 1.6 micrograms per kilogram
Number of tablets - assuming 25 microgram tablets
Actual dose per kg - how much that dose work out at
(Apologies for poor formatting.)
Weight Calculated dose Number of tablets Actual dose per kg
54 86.4 3 1.38
55 88 4 1.81
56 89.6 4 1.78
57 91.2 4 1.75
58 92.8 4 1.72
59 94.4 4 1.69
60 96 4 1.66
61 97.6 4 1.63
62 99.2 4 1.61
63 100.8 4 1.58
64 102.4 4 1.56
65 104 4 1.53
66 105.6 4 1.51
67 107.2 4 1.49
68 108.8 4 1.47
69 110.4 4 1.44
70 112 4 1.42
71 113.6 5 1.76
Hi mrsuns01
I was in the same situation as you. I was under Endo and his junior said I should reduce my Levo from 250mcg to 100mcg as she said I was over medicated. That was before I found this site and I was so ill. I have never had anxiety before but I did then. It was horrendous. Even my regular pharmacist said it’s gonna take months for me to get over it and it did
Anxiety possibly linked to increased dose of Levothyroxine
Carbimazole dose change 
Blood results following increase in Levothyroxine dose
Starting dose too low ?
Increased dose and ectopics 
