Should I take the t4 pill before a bloodwork?

rayban

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I take the eutirox at around 4 am (I go to sleep at 5 am) and wake up at around 2 or 3 pm.

The thing is, bloodwork extractions are done at 8 am here so I will have to wake up early which sucks but social security healthcare only does 8 am extractions.

My question is: Should I take the t4 pill at 4 am considering 4 hours after that I will go to get the test done? I mean, will it have an abnormal result on the test?

But if I don't take it, wouldn't that also not show an accurate result?

I mean ideally I shouldn't be waking up at 8 am since that isn't my normal schelude but I can't do that unless I pay the test for myself to select an hour which I will do but I also want to get this one since I already have the appointment but I want to get an accurate as possible result.
 

Hans

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Your reading at 8am is going to be way off because that's in the middle of your sleep cycle and your circadian rhythm is not in line with the times they test. It's going to be lots of false markers.

But let's say your sleep was in line. Then taking T4 before the test will show you if you're taking enough and if enough T3 is created. Should you thus continue, up dose or add in T3. It's useful to see what next to do.

T4 half-life is between 5-7 days, so you'll need a washout period of 2-3 weeks before you test to see complete organic readings.

I'd say use T4 as you do, but only test if your sleep is fixed. Else false readings all over the place.
 
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rayban

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Your reading at 8am is going to be way off because that's in the middle of your sleep cycle and your circadian rhythm is not in line with the times they test. It's going to be lots of false markers.

But let's say your sleep was in line. Then taking T4 before the test will show you if you're taking enough and if enough T3 is created. Should you thus continue, up dose or add in T3. It's useful to see what next to do.

T4 half-life is between 5-7 days, so you'll need a washout period of 2-3 weeks before you test to see complete organic readings.

I'd say use T4 as you do, but only test if your sleep is fixed. Else false readings all over the place.
So its ok to take it before the test? I was recommended the opposite here:

You should wait to take your T4 just after you have had your blood test done. The timing of your day is different I expect due to your work pattern and that is fine. You take your medication to suit your pattern. But you don't want to take your T4 in the few hours before you get tested because that could skew the result. For many years when I was taking Levo/T4 I took my T4just before getting tested because no one ever told me not to. But I realise that might have contributed to the doctor thinking I was well when I was actually very unwell. So if you hold off taking your T4 until after the blood test you should be ok.

No no no ...never take your T4 or any thyroid meds in the 24hours before a bloodtest


Im going to get the test done since it's free and it tests some other things, but I will get a full bloodwork including thyroid panel appointed in a private lab later at a more normal hour. I do have to start waking up a bit earlier tho. If im supposed to go with an empty somatch then I can't go after eating, and labs typically close at 2 pm and I wake around that hour. So I would need to wake up at like 12:30 pm and get the test done at 1:30pm before they close.
 

sweetpeat

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I think it depends on your purpose for testing.
If you're trying to convince a doctor to raise your dosage, or at least not lower your dosage, then you wouldn't take it before the test so that your levels are at their lowest. This is where the advice to not take it is coming from.

If you don't care about that and want to see the full effect of the dosage, then take it before testing.
 

Hans

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So its ok to take it before the test? I was recommended the opposite here:






Im going to get the test done since it's free and it tests some other things, but I will get a full bloodwork including thyroid panel appointed in a private lab later at a more normal hour. I do have to start waking up a bit earlier tho. If im supposed to go with an empty somatch then I can't go after eating, and labs typically close at 2 pm and I wake around that hour. So I would need to wake up at like 12:30 pm and get the test done at 1:30pm before they close.
As I mentioned, T4 has a 5-7 half-life, so if you take it the day before or an hour before, it's still going to skew the results. I'd say take it as you usually do. Always match your pattern. If you suddenly break your pattern, you're going to get false readings.
 
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rayban

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I think it depends on your purpose for testing.
If you're trying to convince a doctor to raise your dosage, or at least not lower your dosage, then you wouldn't take it before the test so that your levels are at their lowest. This is where the advice to not take it is coming from.

If you don't care about that and want to see the full effect of the dosage, then take it before testing.
So taking it before testing gives you an accurate result?
As I mentioned, T4 has a 5-7 half-life, so if you take it the day before or an hour before, it's still going to skew the results. I'd say take it as you usually do. Always match your pattern. If you suddenly break your pattern, you're going to get false readings.
You mention taking it before will skew the result. I want an accurate result... I want to know if the euthyrox is actually working. This means I take it before the test? Im confused since you mention it will skew the result. Skew is a negative word? I speak French so im not sure about the context.

The people on the thyroid forum say that you should leave at least 24 to 48 hours to get an higher dose. However, how do you know you need an higher dose, if you aren't getting an accurate result? I assume because drs tend to say you are ok even if your TSH is high they don't take it in order to get higher mcg.. makes sense actually. So now im puzzled.. im ordering a bunch of stuff on this lab, not only thyroid, so I would want an accurate result. At the same time, I also would want to test an higher dose.

Btw, when you mean 5-7 half life, you mean hours? isn't it like days?

I found this chart:


498153_1_En_2_Fig1_HTML.png

So if this is what happens with a dose, then you should leave a sufficient gap that avoids that initial peak, so around 15 hours I guess.

If I take it at 3 in the morning, and I get the test done at 1 in the evening, that's 10 hours. So I would still be getting a bit of that initial peak. If I don't take it, then it would be 34 hour gap, which actually shows higher after that initial crash around 12 to 24 hours... thoughts?
 
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Hans

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So taking it before testing gives you an accurate result?

You mention taking it before will skew the result. I want an accurate result... I want to know if the euthyrox is actually working. This means I take it before the test? Im confused since you mention it will skew the result. Skew is a negative word? I speak French so im not sure about the context.

The people on the thyroid forum say that you should leave at least 24 to 48 hours to get an higher dose. However, how do you know you need an higher dose, if you aren't getting an accurate result? I assume because drs tend to say you are ok even if your TSH is high they don't take it in order to get higher mcg.. makes sense actually. So now im puzzled.. im ordering a bunch of stuff on this lab, not only thyroid, so I would want an accurate result. At the same time, I also would want to test an higher dose.

Btw, when you mean 5-7 half life, you mean hours? isn't it like days?

I found this chart:


498153_1_En_2_Fig1_HTML.png

So if this is what happens with a dose, then you should leave a sufficient gap that avoids that initial peak, so around 15 hours I guess.

If I take it at 3 in the morning, and I get the test done at 1 in the evening, that's 10 hours. So I would still be getting a bit of that initial peak. If I don't take it, then it would be 34 hour gap, which actually shows higher after that initial crash around 12 to 24 hours... thoughts?
If you want to see if T4 is working, then take it as you usually take it. If someone wants to see if TRT is working, they test while on TRT. You stop TRT and become hypogonadal and say, hey, the TRT doesn't work! But you were hypogonadal before TRT, what were you expecting when you quit? Same with thyroid. Quit and you become hypo/back to where you were.
Yes, sorry 5-7 days.
 

sweetpeat

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So taking it before testing gives you an accurate result?
I wouldn't say it's more accurate. I would say it depends on whether you're more interested in the peak or the return to baseline. To me, it makes more sense to see what the baseline is doing, since you spend most of your time there. That's how I usually test it anyway, keeping in mind of course that my levels will be higher than baseline for a few hours after taking t4. More important though is how you feel - are temps, pulse, and other symptoms improving.
 
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rayban

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I wouldn't say it's more accurate. I would say it depends on whether you're more interested in the peak or the return to baseline. To me, it makes more sense to see what the baseline is doing, since you spend most of your time there. That's how I usually test it anyway, keeping in mind of course that my levels will be higher than baseline for a few hours after taking t4. More important though is how you feel - are temps, pulse, and other symptoms improving.
It makes sense but @Hans also made a point. What do I do?

Btw, I just bought 2 galistan termometers. How do I make a proper log? I heard mouth+armpit at the same time will get a more accurate result. But If I only test once a day, I don't get the increase and decrease of temperature with food or exercise o a shower for instance.
 

sweetpeat

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It makes sense but @Hans also made a point. What do I do?
I think what Hans is saying is be consistent before you test: take your t4 when you usually take it because that's the routine your body is used to. Then just be aware when you test of whether you're in a peak or not so you know how to interpret the results.

As far as temperature, I'd say be consistent with that as well. Pick one (mouth or armpit) or do both if you want, but try to take at the same time of day. Basal temp only is better than nothing. Checking more than once a day can give you more feedback of course. When I find myself feeling off during the day, I will sometimes check my temp/pulse to help figure out what's going on.
 
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rayban

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I think what Hans is saying is be consistent before you test: take your t4 when you usually take it because that's the routine your body is used to. Then just be aware when you test of whether you're in a peak or not so you know how to interpret the results.

As far as temperature, I'd say be consistent with that as well. Pick one (mouth or armpit) or do both if you want, but try to take at the same time of day. Basal temp only is better than nothing. Checking more than once a day can give you more feedback of course. When I find myself feeling off during the day, I will sometimes check my temp/pulse to help figure out what's going on.
I don't know what to do because on the thyroid forum they say not to take it and leave 24 hours of gap. If I take it im getting that 10 hour peak.
 

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