# TSH - Time of day when tested is IMPORTANT!



## SierraWoods (Mar 12, 2018)

Hi. Newbie here, although I've had Hypothyroidism for over 20 years. Research has shown that the time of day you get your TSH tested is important. TSH is naturally higher in the morning, so those getting afternoon blood tests will often get a TSH reading in the normal range while it would have been higher in the morning, thereby missing a large group of people who should have been diagnosed with Hypothyroidism. This has been true for me - my TSH always indicates Hypothyroidism if I get tested in the AM, and normal if I get tested in the PM.

My question is: I've recently had to adjust my thyroid medicine, so which reading indicates the truer TSH, the morning or the afternoon? If you base it on a morning reading and your TSH is falsely high, you will be prescribed too much Levothyroxine. If you base it on the afternoon reading and your TSH is falsely low, you will be prescribed too little Levothyroxine. Because so many symptoms of Hypo and Hyer overlap (eg. "tired but wired"), it can be hard basing your treatment simply on how you feel. Any thoughts?


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## joplin1975 (Jul 21, 2011)

Yes - ignore TSH and focus on free t4 and free t3 for a more accurate picture of thyroid function. ????


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## Lovlkn (Dec 20, 2009)

TSH is useless once on thyroid hormone replacement although many doctors still insist on using it , especially to adjust doses.

I for one do not have much TSH, regardless of time of lab draw. I do however have somewhat perfect FT-4 and FT-3 labs. My doctor runs TSH but only uses FT-4 and FT-3 for dosing purpose


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## SierraWoods (Mar 12, 2018)

Thanks to both of you. Do you know if free T3 and free T4 are also affected by the time of day?

My last test was taken in mid-afternoon:

TSH = 0.60 (lower than I'd like).

Free T4 = 1.6 (range 0.8 - 1.8)

Free T3 = 2.7 (range 2.3 - 4.2)

Since my free T4 was in the high-normal range and my free T3 was in the low-normal range, does it make sense to increase my dose just a bit to get the free T3 into the high-normal range? Even though that could make my TSH plummet to close to zero? I cannot base my dose just on how I feel because I have some of the same symptoms when I'm a bit hypo and when I'm a bit hyper.

This place is wonderful. I've been reading posts and learning so much. I hope I can contribute something worthwhile some day.


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## joplin1975 (Jul 21, 2011)

Well, your hormone levels do fluctuate during the course of the day. T4 tends to be more stable, while t3 tends to be higher in the morning and lowers as the day goes on. But, again, those are general trends.

Those numbers also can be impacted by when you take your meds in relation to when you have your blood drawn. That is, you might get higher free t4 numbers if you have your blood drawn shortly after you take your meds.

In you case, I would think about making a slight decrease to you t4 meds and seeing if you doctor will add in Cytomel to increase your t3.


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## Lovlkn (Dec 20, 2009)

I suggest the same.

Decrease T4 hormone dose and add Cytomel or lilothyronine. 5 mcg to start split 6 hours apart. 
Retest in 6 weeks.


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## SierraWoods (Mar 12, 2018)

Thanks for the suggestions.

I tried Cytomel once, years ago, and it made me so hyper I couldn't stand it. I don't recall the dose or number of times per day. I heard that a compounding pharmacy can custom make your Cytomel/T3 in a sustained release formula so that you don't get the instant hyper surge. Have any of you heard of this?

Also, if I follow your suggestions, do I start taking the Cytomel as soon as I lower my Synthroid, or do I first lower Synthroid for six weeks and then start the Cytomel? So confusing.


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## joplin1975 (Jul 21, 2011)

I'd lower your synthroid and start Cytomel, but break up your doses so that you are taking very very low doses multiple times a day.

There shouldn't be any need to lower your synthroid and do that for six weeks.


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## SierraWoods (Mar 12, 2018)

I'm going to try to find a good doctor who will work with me. Mary Shomon's website has a page with recommended doctors - I hope I can find one near me.

One more question, please - I've been having a problem of waking up with adrenaline surges for the last eight years. It's extremely uncomfortable and sometimes, the hyper feeling will last throughout the day. On the other hand, there are days where I crash in the afternoon, especially if I am particularly active. It's confusing because the morning hyper feelings indicate that I have too much thyroid hormone (Synthroid) but the afternoon crashes indicate the I don't have enough. So frustrating. If I lower my Synthroid enough to stop having the morning adrenaline rushes, can I just take the Cytomel one time in the afternoon to get me through those few hours (I'm assuming Cytomel becomes active in the body pretty quickly.)? Or do I have to take it several times so that it stays in my system? I'm afraid if I do that, the morning adrenaline will get worse. :-(

Thanks again. You guys are great!


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## joplin1975 (Jul 21, 2011)

I'll have to defer to my friends who take cytomel.

Those "adrenaline surges" are actually a result of antibodies.


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## SierraWoods (Mar 12, 2018)

Super Gold Veteran, do you mean thyroid antibodies? I was tested for TGAb and TPO thyroid antibodies and they both came out negative. I was retested just a couple months ago and they were still negative. Could you explain, please, or point me in the right direction to do some research?

Thanks!


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## joplin1975 (Jul 21, 2011)

Yes, thyroid antibodies. Was your result actually zero or was it within range? When were they last tested? Was TSI tested?


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## SierraWoods (Mar 12, 2018)

Super Gold Veteran, I was tested twice - nine years ago and again, just a few months ago. Here are the results:

Antithyroglobulin (2009): <20 IU/mL

(2017): 1.1 U/mL (ref range - 0.0 - 4.0)

Thyroid Peroxidase AB (2009): <10 IU/mL

(2017): <28 Um> (ref range <60)

If the antibodies (even though a small amount) are causing the morning adrenaline surges, can you please tell me how that happens? In other words, what is the mechanism by which my adrenal glands would be producing the excess surges of adrenaline (or noradrenaline)? I'm trying to understand this. Thanks again.

8 years ago, I was tested for "Thyroglobulin Antibodies". Result: <20 IU/mL

I was also tested for "Thyroid Peroxidase Antibodies". Result: <10 IU/mL

Just a few months ago, I was retested for "Antithyroglobulin". Result: 1.1 U/mL (ref range - 0.0 - 4.0)

Also, for "Thyroid Peroxidase AB". Result: <28 Um> (ref range <60)


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