Hi and thanks for adding me to the group. Mum has been hypothyroid for many years and is taking 150mcg of thyroxine daily. Her recent blood test shows free t4 at 24.8 and tsh at 0.17. The Gp called her and said it seems that she's now hyperthroid.
The only thing that's changed is that she recently had a heart attack and is on heart medications and she's taking a biotin supplement.
The Gp checked her neck and there's no swelling, lumps or bumps, eyes are fine and no tremor etc. The advice from on call endo was to stop biotin, refer to endo, reduce thyroxine to 100mcg and recheck bloods in 1 month.
I'm inclined to think that this is down to the biotin supplement but wondered if anyone else has had a similar experience?
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Samanthauk
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The Gp called her and said it seems that she's now hyperthroid.
That's impossible. If one is hypOthyroid it's not physically possible to become hypERthyroid, although it is possible to be overmedicated. GP should learn the difference.
Her recent blood test shows free t4 at 24.8 and tsh at 0.17.
Without reference ranges we're only guessing, so I expect TSH is below range and FT4 is above range and that's what's freaking the GP out.
she's taking a biotin supplement.
If she didn't leave this off for 7 days this could have caused false results. When biotin is used in the testing procedure and we also take a biotin supplement, then we have to leave it off to be sure we don't get false results. If she didn't leave it off then she should tell her GP that because she's taken biotin the results are very likely false so she needs a new test after leaving it off for 7 days. All labs know this, some even put it on the report when sending results back.
Always advised here, when having thyroid tests:
* Blood draw no later than 9am. This is because TSH is highest early morning and lowers throughout the day. If looking for a diagnosis of hypothyroidism, an increase in dose of Levo or to avoid a reduction then we need the highest possible TSH
* Nothing to eat or drink except water before the blood draw. This is because eating can lower TSH and coffee can affect TSH.
* Last dose of Levo 24 hours before the test, take that day's dose after the blood draw. This is because if you take your Levo before the blood draw the test will measure the dose just taken and show a false high. If you leave longer than 24 hours the result will show a false low.
* 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).
These are patient to patient tips which we don't discuss with phlebotomists or doctors.
Your mother's doctor might not be aware of the effects of biotin on testing so you might want to print out some info on the subject and give it to him.
Since neither doctors nor patients know which testing machines and testing protocols are affected by the presence of biotin in the blood samples being tested it is always wise to stop taking any supplements with biotin in for a week before testing. But obviously this is difficult if we don't get given any warning that blood is going to be taken for testing.
Since your mother is hypothyroid (despite her doctor declaring she is hyperthyroid which is stupid), at the very most she might benefit from getting her dose of Levo reduced very slightly. But doctors panic at the slightest sign of a thyroid hormone result being over the range by a little bit or a TSH being under the range by a little bit and they have a tendency to over-react, sometimes to an absurd degree. So your mother must try and prevent that happening.
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Another problem that effects the results of thyroid tests is the time of day the test was done.
TSH is at its highest during the night and at its lowest in the afternoon. Obviously blood testing is done during office/surgery hours so the best time to get blood taken is as early in the morning as possible, and by 9am at the latest.
Free T4 is also going to be at a peak a couple of hours after the patient takes their Levo. So, it is always a good idea to leave 24 hours between the last dose of Levo and blood being taken.
So, what time of day was your mother's blood taken? And had she taken her Levo that day? And had she had breakfast? (Because eating will also lower TSH.)
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I've just realised that SeasideSusie has said all this already, and I didn't notice.
Yes, I had a higher test result after my GP sprung a test on me while I was taking Bcomplex with biotin...she brushed off my suggestion that the result would be skewed!
I'm waiting to be retested as per guidance here!
Your medic is wrong to suggest your mum is now hyperthyroid ( not possible!)
what she should have noted instead was possible overmedication.
Difficult to say without ranges.
I don't suppose FT3 was tested, that is the important reading and along with FT4 can tell us if conversion is poor.
High FT4 with low FT3 suggests poor conversion. and a small dose of T3 can help.
For full Thyroid evaluation your Mum needs 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
Low vitamin levels tend to lower TSH
Low vitamin levels are more common as we age and especially common on levothyroxine
Ask GP to test vitamin levels or test privately
Recommend you get retesting done BEFORE reducing levothyroxine
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 .
Last dose of Levothyroxine 24 hours prior to blood test. (taking delayed dose immediately after blood draw).
This gives highest TSH, lowest FT4 and most consistent results. (Patient to patient tip)
Private tests are available as NHS currently rarely tests Ft3 or thyroid antibodies or all relevant vitamins
Hi Samantha, this really is the story of many people. Your mum really could do well to see a professional in all this. They have no idea how to balance hormones in the NHS. My doctor is in Brussels, you don’t have to go there, she sends a blood pack and can then speak to your mum when she has the results on Skype. She is excellent and looks at all hormones and every aspect of the body. Please DM me for details if you need to know more. Thank you.
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