Just had some lab work done and did not take my np throid the night before as usual. TSH is 7.5 (.33-5.33) last year I did the same and it was 8.5. 3 years prior I was taking meds in the morning and took my meds before testing and had results under 2. Could the results really be that off from about 36 hrs without? Or is this an issue with reformulation. I do feel tired in the mornings but then am pretty much the same all day as previous years.
Any ideas? I feel I am not getting an accurate test reading by not taking the pill as usual. Should I start taking a bit more? Last time I tried that I had an all day headache and felt nauseous. And that was adding about 10-15mg more (splitting pill so inaccurate). My daily dose and for several years is 50 mg np throid
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ChrisCh
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Stopping or taking your meds before the blood draw won't have any effect on your TSH - unless you leave them off for about a month!
Taking your meds before the blood draw - or leaving too long a gap between the last dose and the blood draw - will affect your FT4 and FT3.
Leaving 36 hours is much to long. And will give you false low FT4/3 When you're taking NDT, you should leave a gap of 8 to 12 hours only. That will give you your normal circulating level of FT3. The FT4 isn't that important.
Thank you for that information. I only had the TSH tested this time. So I wonder what is causing such a rise from previous years. Maybe I’ll try titrating up a bit. How long would you say it takes to actually feel a difference?
Feel a difference in what? The TSH itself doesn't make you feel anything. It is the FT3 that causes symptoms when it's too high or too low. So, you really need that tested - especially as you are on NDT. The TSH doesn't tell you anything much at all, despite what doctors think.
What is probably causing the rise is that your thyroid is failing even further. It's unrealistic to think you can stay on the same dose forever and still feel well. The disease evolves.
In fact now that I think about it these higher numbers is what I had from about 8 years ago when I started taking thyroid meds. Wonder why I’m bothering?
Chiming in here: I read this advice all the time - take meds 24 hours prior for T4, 12 hours prior for T3. But what about when your T4/T3 med is compounded into a single pill and you can't take them separately? When should the last dose be taken?
Usually when correctly treated on NDT TSH is under one, and FT3 in top third of range
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
Do you have Hashimoto's?
When were vitamin levels last tested?
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 .
Thanks but I take levothyroxine first thing in the morning between 7 and 7.30 am but it is just one pill. How can I split my dose ? normally here blood test are around 09.00 thanks
TSH is fairly slow to change, so it probably won't be impacted by when you take your tablets. FreeT4 and freeT3 are a more direct measure of how much hormone is in your blood, so they will change quite a bit.
Our bodies change quite a bit over time in how they use thyroid hormone, so it's not too surprising your results from years ago aren't the same as they are today. This is why it's important to get tested and adjust dose every year or so even once we reach an ideal dose. Your current results suggest you're very undermedicated, so you'd likely feel better with an increase.
The irony is that those, who have not had much experience of this site, have been able to be brainwashed by GPs into believing that TSH is the be-all and end-all. Instead of it being of little interest.
Please just bear in mind that it’s how you feel that’s important.
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How long before blood test to stop B12?
should meds be taking before blood test
Help please with meds before blood test.
Major difference with medichecks and nhs tsh same day test 
