# Morning or afternoon bloodwork?



## dovetail (May 9, 2013)

I've always got my bloodwork done in the morning but I read somewhere it may be better to get it done in the afternoon? Any thoughts? I was diagnosed with Hashi's a year ago and still have trouble with energy.


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## bigfoot (May 13, 2011)

When I do labs, I generally get them drawn first-thing in the morning, *before* taking any morning dose of thyroid medication (well, any medication, really). When do you take your thyroid medication?

FYI, the TSH spikes the most in the wee early-morning hours. So, in theory, getting labs drawn in the A.M. would show more of a deficiency than in the P.M.


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## CA-Lynn (Apr 29, 2010)

Frankly, I don't think it makes a bit of difference what time of day or whether you've taken your pill before the test.

http://thyroid.about.com/od/gettestedanddiagnosed/a/tshtests.htm


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## joplin1975 (Jul 21, 2011)

I've had mine taken first thing in the morning, at lunch, and after work. The results are generally all about the same.

Said with the qualification that I'm on t4 only meds.


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## Andros (Aug 26, 2009)

dovetail said:


> I've always got my bloodwork done in the morning but I read somewhere it may be better to get it done in the afternoon? Any thoughts? I was diagnosed with Hashi's a year ago and still have trouble with energy.


If you are on T4 only, I don't imagine it would matter but if you are taking exogenous T3, it would matter a lot.

Liothyronine (T3)
is almost totally absorbed, 95 percent in 4 hours.
http://www.frx.com/pi/armourthyroid_pi.pdf

This would mean it peaks in 4 hours and that could mess you up if you get a "temporary" high reading.


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## sjmjuly (Mar 23, 2012)

I am on combo T4/T3 and it makes a HUGE difference. If I have blood drawn in the morning, my Free T3 is well in range. If blood is drawn later in the day, My T3 is tanked. This is why alot of doctors argue the Free T3 blood test request. Since it goes up and down so much, they don't feel its an accurate gage.


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## dovetail (May 9, 2013)

Thanks everyone for your thoughts. I'm on T4 meds and I switched to taking them at night a couple mths ago.


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## Lovlkn (Dec 20, 2009)

sjmjuly said:


> I am on combo T4/T3 and it makes a HUGE difference. If I have blood drawn in the morning, my Free T3 is well in range. If blood is drawn later in the day, My T3 is tanked. This is why alot of doctors argue the Free T3 blood test request. Since it goes up and down so much, they don't feel its an accurate gage.


Do you by chance take your T-3 med before your morning lab draw?

I have my labs done as early in the morning as possible as I do not take my nightly dose of Unithroid or Cytomel and want to take it as soon as possible in my day to not throw myself off too much.


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## Andros (Aug 26, 2009)

dovetail said:


> Thanks everyone for your thoughts. I'm on T4 meds and I switched to taking them at night a couple mths ago.


Well; stay the course and be consistent. That's the main criteria.


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## sjmjuly (Mar 23, 2012)

Lovlkn said:


> Do you by chance take your T-3 med before your morning lab draw?
> 
> I have my labs done as early in the morning as possible as I do not take my nightly dose of Unithroid or Cytomel and want to take it as soon as possible in my day to not throw myself off too much.


I take Naturethroid which is a combo med so you can't split the T4 from the T3. I take it at 4:00 AM and this is ALWAYS before I have my blood drawn. If I go early in the morning, my T3 is normal range. If blood is drawn later in the afternoon my T3 is tanked since it has a short shelf life. This is why most doctors hate the Free T3 test. It changes so much during the day they find it unreliable to dose from. I kinda learned this from experience. Bumped my dose because my T3 was tanked and holy cow did I pay for that with mean, nasty heart palps!


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## comanchesue (Jan 15, 2013)

TSH will be higher in the morning and lower in the afternoon. Mornings are best because an afternoon reading may be low enough that the doc will think it's always that low. This could cause no meds, or prohibit a needed med increase. Docs are generally focused only on TSH.

http://www.naturalmedicinejournal.com/article_content.asp?edition=1&section=3&article=386

Using the current reference range of TSH (0.4-4.0 mU/L), an afternoon blood sample would lead to a missed diagnosis in 50% of those with subclinical hypothyroidism (P<0.0001)


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