I was going to test my bloods on Monday the 29th of August but I received an email from Medichecks saying not to post any samples between the 25th of August and the 1st of September due to a post strike so I won’t be able to do it until Friday the 2nd of September,I’ll just need to pay for the guaranteed next day delivery as I fly out to turkey that day,the problem I have is now I’ve been moved to the capsules for T3 I only have enough tablets to give me the 5mcg up until the 2nd of September so I’ll either need to up my dose or drop it,I’m currently taking 100mcg of levo and 15mcg of liothyronine so would be grateful for any advice.
I also noticed in my Medichecks email today that they say to stop B12 two weeks before the test and there’s B12 in the b complex I take🤷♀️If anyone could advise on this also please🙏
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PrincessAnnie
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It says on there F&Q section if sending it on a Friday to pay for the next day delivery so it arrives at the lab on the Saturday before they close at 3pm,I might message them to confirm if it’s ok.
Medichecks have been inconsistent with the advice given about stopping supplements before testing.
A couple of years ago this is what they told one of our members who questioned their advice about biotin:
Because biotin is an ingredient used in many lab hormone test kits this can interfere with the measurement of thyroid hormones
It does this in an inconsistent way, causing falsely elevated results from some labs, and falsely low results from others. We recommend stopping biotin for one week prior to blood tests.
A little while later they altered their instructions to include information about leaving B12 off for one week but there was no information about leaving off biotin. I contacted them for clarification and they replied with the following:
I have discussed your query with our medical director he has advised the below:
Biotin supplements.
Biotin can affect the results of any test which relies on antibodies to perform the measurement. It is wise to assume that any hormone or vitamin test will be affected, which means that the majority of our test panels can be affected by biotin supplements.
The issue with Biotin only affects people who take high dose biotin supplements. The manufacturers of the laboratory tests define this as 5000 mcg per day or more.
We are recommending people do not take high dose biotin supplements for 24 hours prior to having their blood drawn.
If they are taking high dose biotin for medical reasons (e.g. multiple sclerosis) then a shorter washout period of 8 hours can be used.
Vitamin B12 supplements.
The answer to this depends upon what they are wanting to assess.
To work out whether B12 supplements are meeting the body's requirements we recommend not taking supplements for one week prior to having their blood drawn.
If a customer wants to assess whether they have an underlying B12 deficiency then it can take months (and potentially up to two years) for levels to fall to their natural levels after stopping supplementation. In this instance we would not recommend.
I can also confirm this information will be displayed on our test instructions in the near future.
I don't do my thyroid/vitamin panel with Medichecks so I don't know whether they do include this information about B12.
My understanding is that to get a baseline B12 level to see what you are holding on to then you leave any B12 supplement off for 4-5 months. If you are taking B12 and want to see if the dose you are taking is achieving a good level or whether you need to increase or lower the dose then you continue taking it up to the day before the test. I don't think leaving it off for 2 weeks is helpful, I think it would give a slightly lower level than normal. I would take B12 up to the day before the test, on the day of the test I would take it after the test. This is just my opinion.
Also, they have changed their minds a couple of times as to how long biotin should be left off.
I do my thyroid/vitamin panel with Blue Horizon and their instructions are:
Please Note: Because of the potential for interference with test results, samples should not be taken from patients taking BIOTIN in excess of 5 mg per day until at least 8 hours following the last biotin dose.
No mention of stopping B12.
So I would stop your B Complex for 3-7 days before the test (7 days for large amounts of biotin such as 5mg or 10mg found in hair/nail supplements or stand alone biotin supplements) and 3 days should be enough for the smaller amount in a B Complex, eg arund 500mcg.
As for B12, don't worry about it unless you're taking a B12 stand alone supplement and want a baseline.
Thanks for that,I don’t take B12 stand alone supplement it’s just in the vitamin b complex I take,so I should stop taking that 3 days before the test and not 7?
I’ve decided to just wait to do my test,I’ll start my new dose on the 3rd of September and wait 8 weeks then test,I have 120 days from date of purchase to use the test.
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