Does Your GP need to advise you not to take the thyroid tablet the day you go for your blood test
I have taken it twice The first time I was told Vitamin D3 is low and was given a strong dose and now have to take it life long The test I had in between that not taking the tablet came back normal when asked to reduce the dose was told to wait for my next test which I done this month and took the table This time I am at ways to take 100 MG instead of 50 MG and also consider myself diabetic did I do my test in August kindly advice and also how do I attach the blood test results I can only attach one at a time
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Annaadam12
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The past 5 days. Not always the same brand l have my blood test this month and I have a copy from the GP he has advised to consider myself Diabetic and increased the thyroid tablet l have a fasting test in August
Not always the same brand l have my blood test this month
Dose levothyroxine is typically increased in 25mcg steps
You might find going from 50mcg to 100mcg is too much
Suggest you might increase to 75mcg for first 2-3 weeks before increasing to 100mcg
Bloods should be retested 6-8 weeks after any dose change or brand change
Once you know which brand of levothyroxine suits you best make sure you always get same brand
Many patients do NOT get on well with Teva brand of Levothyroxine. Teva contains mannitol as a filler, which seems to be possible cause of problems. Teva is the only brand that makes 75mcg tablet. So if avoiding Teva for 75mcg dose ask for 25mcg to add to 50mcg or just extra 50mcg tablets to cut in half
But for some people (usually if lactose intolerant, Teva is by far the best option)
Teva, Aristo and Glenmark are the only lactose free tablets
Most easily available (and often most easily tolerated) are Mercury Pharma or Accord
Accord is also boxed as Almus via Boots, and Northstar 50mcg and 100mcg via Lloyds ....but doesn’t make 25mcg tablets
Physicians should: 1) alert patients that preparations may be switched at the pharmacy; 2) encourage patients to ask to remain on the same preparation at every pharmacy refill; and 3) make sure patients understand the need to have their TSH retested and the potential for dosing readjusted every time their LT4 preparation is switched (18).
Levothyroxine is an extremely fussy hormone and should always be taken on an empty stomach and then nothing apart from water for at least an hour after
Many people take Levothyroxine soon after waking, but it may be more convenient and perhaps more effective taken at bedtime
No other medication or supplements at same as Levothyroxine, leave at least 2 hour gap.
Some like iron, calcium, magnesium, HRT, omeprazole or vitamin D should be four hours away
(Time gap doesn't apply to Vitamin D mouth spray)
If you normally take levothyroxine at bedtime/in night ...adjust timings as follows prior to blood test
If testing Monday morning, delay Saturday evening dose levothyroxine until Sunday morning. Delay Sunday evening dose levothyroxine until after blood test on Monday morning. Take Monday evening dose levothyroxine as per normal
REMEMBER.....very important....stop taking any supplements that contain biotin a week before ALL BLOOD TESTS as biotin can falsely affect test results - eg vitamin B complex
Diabetes diagnosed by high HBA1C
HBa1C levels likely to improve once on correct levels of levothyroxine
50mcg is only a starter dose levothyroxine. So hardly surprising you were left hypothyroid on starter dose
Does Your GP need to advise you not to take the thyroid tablet the day you go for your blood test
They should - but they almost never do - in fact some of them advise patients to do the exact opposite, and take their Levo before the blood test. This will mean that if Free T4 is tested the level will be the highest it is likely to get.
Another thing to take into account is the circadian rhythm of TSH - it is best to get a test done by 9am at the latest, but many doctors will force patients to get their TSH tested in the afternoon when TSH is at its lowest.
Just spoke with the GP Dr unfortunately my doctor was not available today the lady doctor that I spoke today I told That you’re not supposed to take the Thyroid tablet the day you go for your test and she said I’ve never had this in all my life just take the hundred MG for now and after six weeks you can get another test done and it’s up to you if you don’t want to take the tablet on the day of your test
Come back with new post once you get blood test redone 6-8 weeks after being on 100mcg and always same brand
guidelines on dose levothyroxine by weight
Even if we frequently don’t start on full replacement dose, most people need to increase levothyroxine dose slowly upwards in 25mcg steps (retesting 6-8 weeks after each increase) until eventually on, or near full replacement dose
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.
Traditionally we have tended to start patients on a low dose of levothyroxine and titrate it up over a period of months. RCT evidence suggests that for the majority of patients this is not necessary and may waste resources.
For patients aged >60y or with ischaemic heart disease, start levothyroxine at 25–50μg daily and titrate up every 3 to 6 weeks as tolerated.
For ALL other patients start at full replacement dose. For most this will equate to 1.6 μg/kg/day (approximately 100μg for a 60kg woman and 125μg for a 75kg man).
If you are starting treatment for subclinical hypothyroidism, this article advises starting at a dose close to the full treatment dose on the basis that it is difficult to assess symptom response unless a therapeutic dose has been trialled.
Thank you so much for response l really appreciate it but to be honest with you I refuse to take 100mg instead of 50mg the reason why because I took the thyroid tablet on the day of the test that’s why the thyroid is high and I also have to consider my self Diabetic till I have my Diabetes test in August taking the 100 mg for 5 days made me chocked twice on food I honestly think I should take it further who knows I maybe taking a over dose
Your doctor has advised you to increase your dose levothyroxine from 50mcg to 100mcg
Perhaps increase to 75mcg initially for 6-8 weeks (cutting 50mcg tablets in half to make 25mcg tablets)
Typically dose levothyroxine is only increased upwards in 25mcg steps
Bloods should always be retested as early as possible in morning before eating or drinking anything other than water and last dose levothyroxine 24 hours before test
NHS England Liothyronine guidelines July 2019 clearly state on page 13 that TSH should be between 0.4-1.5 when OPTIMALLY treated with just Levothyroxine
Note that it says test should be in morning BEFORE taking levothyroxine
I may have missed something here, but i wonder if you've got things confused. If your thyroid was high (following you taking the pill prior to blood test) then they wouldnt have put it up. Choking is a hypothyroid symptom. We can't tell where your thyroid is because there isnt a thyroid blood test on the list you posted.
I should add that im having a bad day, so apologies if i have the wrong end of the stick
Apologies Accepted. We all do have those days 😊Anyway what l am trying to say is The previous blood test I had was normal because I forgot to take the thyroid tablet before the test and this time I did take the thyroid tablet and I get a phone call saying I have to increase the tablet from 50 mg to 100 mg and consider myself Diabetic
Time of last dose only affects fT4 results .. it does not affect TSH result.
We can't see your thyroid blood test results on that picture you put up.. just the bottom of a comment about. "... TSH indicating likely under replacement with thyroxine or compliance concern"
is there a TSH result above that comment ?
Is there a result for fT4 anywhere, or did they just do TSH ?
The previous blood test I had was normal because I forgot to take the thyroid tablet before the test So...this would have had the effect of giving a lower fT4 result .. (it would not effect the TSH result)
and this time I did take the thyroid tablet
So if it was about 3/4/5 hours before the test, then this will have given a higher fT4 result than the previous one (even though you average daily fT4 level was actually the same as previous test) . But This will not affect TSH either.
(*obviously if it was only half an hour before your test then it would not have had time to get from stomach to blood so fT4 would still look the same as if you hadn't taken it.)
So the point is .. you have been advised to increase dose based on last result which was done at the highest point for fT4 ( ie. done after taking that whole days dose) .. however we don't know if your GP even tested or looked at fT4 . they may have just done TSH.. which is not affected by time of last dose, and if your TSH is too high you do need an increase.
And even if they are looking at fT4 .. the last result was possibly higher than your real average level .. so IF testing after taking tablet had taken your fT4 result over range, then the Gp would have asked you to reduce dose not increase it.
It seems most likely that it was your TSH result that was too high , and it is because of this that you have been asked to increase your dose of T4.. so either way .. it's not a mistake .. you do seem to need an increase..... and then you need thyroid bloods need testing again after 6 weeks on the new dose ,to see if TSH has lowered by enough.. is this what your august blood test is for ?
Did you see slowdragons comment ... "Diabetes diagnosed by high HBA1C, and HBa1C levels are likely to improve once on correct levels of levothyroxine"
(*as others had said , it might have been a better idea to increase by 25ncg at first to see results rather than 50mcg all in one go, as some people will find that too much of a change all at once)
agree with you. I have had a word with my GP about this and he said health unlocked are not Doctors he said it has to do with my body weight and that’s why he has increased it to 50 mg more which I am taking at the moment. Will be going for a blood test soon but he has advised me to take the tablet before my test
no one here is a Doctor , just people with lots of experience and knowledge about thyroid treatment and research.
If the GP is only testing TSH, then it doesn't make any difference if you take the tablet on the day of the test or not. (this might be the case for you ~ the last time you posted thyroid results only the TSH was tested )
BUT if they also test fT4, then the fT4 result IS affected by how long before the test you took the last tablet. ~ if you took the last tablet just a few hours before the blood test, the fT4 result will be much higher than if you took the last tablet 24hrs before the test... so in order to make the new fT4 test a true comparison with the last fT4 test you need to be consistent about the gap between the last dose and the test.
The best way to be consistent is to take your tablet the day before, always have an early morning blood test , and then take that days tablet straight after the test .. this gives a consistent 24hrs each test , and so the GP can properly compare that fT4 result to the last one.
If the GP does NOT test fT4 , but ONLY tests TSH .. then it doesn't matter what time you take the last tablet .. because TSH does not react instantly to taking the tablet , whereas fT4 level goes up sharply as soon as the tablet is absorbed from you stomach , and then gradually goes down until you take the next tablet.
Because you never know whether the NHS will test fT4 or not.. it is best to assume they might do ...... and this is why we always say "leave 24hrs from last dose., and do the same every test"
Most Doctors are ONLY taught about TSH tests, and this is why so many of them think it doesn't matter what time you take the last tablet... they simply don't know that fT4 level shows a sharp increase shortly after taking the tablet .... but it does ..and if they were interested enough to look it up they would find out we are correct.
Thank you so much for amazing Explanation I am going to have a blood test for EDTA and SST today And haven’t taken the tablet but took it yesterday kindly advise
I agree with you. I have had a word with my GP about this and he said health unlocked are not Doctors he said it has to do with my body weight and that’s why he has increased it to 50 mg more which I am taking at the moment. Will be going for a blood test soon but he has advised me to take the tablet before my test
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