I recently posted asking some questions about my Thyroid panel. I had these tested 2 months ago. Originally, my T4 came back as 11, with the preferred range being 12-22. The doctor wanted me to come back in 8-12 weeks for a retest.
I went last week, in the mid afternoon without fasting (not sure if this is good for thyroid panel), and my T4 today came back as 12.1, just inside the 12-22 range. So the doctor has decided not to re-test me or specify anything I can do to maybe help my thyroid move in the other direction.
I still have many of the symptoms of an underactive thyroid and I’m just wondering if you all think it’s best to keep getting tested every once in a while, or is 11-12 not optimal but maybe an acceptable range?
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rubyroo23
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I went last week, in the mid afternoon without fasting (not sure if this is good for thyroid panel), and my T4 today came back as 12.1, just inside the 12-22 range.
Suggests possible Central Hypothyroidism which is where the problem lies with the hypothalamus or the pituitary rather than a problem with the thyroid gland. With Central Hypothyroidism the TSH can be low, normal or slightly raised, and the FT4 will be low.
TSH is a pituitary hormone, the pituitary checks to see if there is enough thyroid hormone, if not it sends a message to the thyroid to produce some. That message is TSH (Thyroid Stimulating Hormone). If there is enough hormone then there's no need for the pituitary to send the message to the thyroid so TSH remains low.
In Primary Hypothyroidism, which is where the thyroid fails, the TSH will be high.
However, with Central Hypothyroidism the signal isn't getting through for whatever reason so the message isn't getting through to the thyroid to produce hormone, hence low FT4. It could be due to a problem with the pituitary (Secondary Hypothyroidism) or the hypothalamus (Tertiary Hypothyroidism).
As Central Hypothyroidism isn't as common as Primary Hypothyroidism it's likely that your GP hasn't come across it before.
Your GP can look at BMJ Best Practice for information - here is something you can read without needing to be subscribed:
You could do some more research, print out anything that may help and show your GP.
You may need to be referred to an endocrinologist. If so then please make absolutely sure that it is a thyroid specialist that you see. Most endos are diabetes specialists and know little about the thyroid gland (they like to think they do and very often end up making us much more unwell that we were before seeing them). You can email ThyroidUK at
tukadmin@thyroiduk.org
for the list of thyroid friendly endos. Then ask on the forum for feedback on any that you can get to. Then if your GP refers you, make sure it is to one recommended here. It's no guarantee that they will understand Central Hypothyroidism but it's better than seeing a diabetes specialist. You could also ask on the forum if anyone has been successful in getting a diagnosis of Central Hypothyroidism, possibly in your area which you'll have to mention of course.
Central Hypothyroidism was mentioned to you in a reply to your previous post here
I suggest that you check out the links above and present some of the "evidence" to your doctor, backed up by the information in the links.
As for thyroid tests, we always advise:
* Book the first appointment of the morning, or with private tests at home no later than 9am. This is because TSH is highest early morning and lowers throughout the day.
In fact, 9am is the perfect time, see first graph here, it shows TSH is highest around midnight - 4am (when we can't get a blood draw), then lowers, next high is at 9am then lowers before it starts it's climb again about 9pm:
If we are looking for a diagnosis of hypothyroidism, or looking for an increase in dose or to avoid a reduction then we need TSH to be as high as possible.
* Nothing to eat or drink except water before the test - have your evening meal/supper as normal the night before but delay breakfast on the day of the test and drink water only until after the blood draw. Certain foods may lower TSH, caffeine containing drinks affect TSH.
[* If taking thyroid hormone replacement, last dose of Levo should be 24 hours before blood draw, if taking NDT or T3 then last dose should be 8-12 hours before blood draw. Adjust timing the day before if necessary. This avoids measuring hormone levels at their peak after ingestion of hormone replacement. Take your thyroid meds after the blood draw. Taking your dose too close to the blood draw will give false high results, leaving any longer gap will give false low results.]
* If you take Biotin or a B Complex containing Biotin (B7), leave this off for 7 days before any blood test. This is because if Biotin is used in the testing procedure it can give false results (most labs use biotin).
biotin use can result in falsely high levels of T4 and T3 and falsely low levels of TSH
These are patient to patient tips which we don't discuss with doctors or phlebotomists.
Hi I'm having trouble getting thyroid management too.Had a lengthy conversation a couple of days ago with surgery pharmacist and I sent him 2 letters about thyroid UK have said and MMR results he said interesting but because I'm in the range just he won't up my levo.I not felt well for years and have been on 25mg levo for 15 years and my TSH was just over 5 on nhs test and just under 4.88 on MMH private test.So frustrating.
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