Pernicious Anaemia Society
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Has anyone had Active B12 test via post at St Thomas please, bit confused by instructions!

Hi, just wondering if anyone has had their Active B12 tested via this hospital please?

My tub has arrived today ( presuming my doctor supplies the yellow top serum tube) and it says before shipping it is recommended specimens be removed from the clot. serum may be shipped ambient ( maximum 16 hours in transit) at + 2-8C ( wet ice) -stable for up to three days or frozen (dry ice).

Am a bit confused about this, so thought I'd ask on here before having to contCt the hospital again on Monday.

Thanks very much...:)

7 Replies

Who will be taking your blood? Surely they will also be able to do the required preparation.

If I've got this correct then - The blood is taken into the yellow tube (normally a vacutainer nowadays). This tube contains a clotting agent. The tube is inverted a few times to mix the blood and the clotting agent and is then centrifuged to separate the serum from the clot. The serum is then transferred to another tube.

Obviously this is not something you can do at home. I would imagine they expect you to attend a private phlebotomist who can do all this. Or to actually visit St Thomas' if possible.


Hi fbirder, thanks again for your time and explanation. My Doctor has said I can have my blood taken at the surgery, so I presume they can do the required there. I just wasn't sure about getting it back to them after reading about the delivery requirements, but will have to check on Monday.

Thank you, you've helped a lot this week...


I had the same concerns and asked about it, but was assured no special processing was necessary. So all that happened was that the blood was taken as normal at the GP surgery, correctly labelled, no extra processing, and then I packaged it up and took it to the post office. I used extra packaging and I paid extra for next day delivery as I was worried about the time factor.

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Thank you, that's a relief. Did you package yours into a box for extra protection? I presumed I'd paid for quick delivery, did you pay for the guaranteed by 9 am delivery please?

Also, can I ask how long you waited for the results?

Thanks ever so much...:)


Yes, packed in a box and I used bubble wrap. I paid for the guaranteed delivery and I emailed the hospital to say I had done this - got a reply to say they would look out for it.

I waited ages for the results and when I asked they said they had sent them to the surgery, but the surgery said they had not received them - not sure what happened exactly, but surgery may have missed them as it was not their usual lab.


Thanks very much...I'm just looking at the difference in costs as it's 3 times as much for the 9am, but guess will have to try and work it out between the post office and docs surgery for timing.

What an absolute pain having your results lost. Not what you'd expect after having to pay especially! I forgot to ask about result times, what with trying to sort out in the first place where to have the test, trying to convince the doctor, then trying to discover whether it's ok to have after now having 3 lots of antibiotics for infections ( seems like that's blown the MMA test for a while!) I forgot about the rest! Haha.

Was just reading through your posts and found you had the same concerns as me, so sorry you've had to repeat them! Sounds we are similar, CFS diagnosis but trying to find other explanations. I've discovered low vit d, low ferritin and b12 in the grey area 261, which dropped from 456 in 9 months, over the last year from researching on are you getting on now, is the b12 helping with your migraines and symptoms? Hope so...

Thanks again :)


I think the 16 hours isn't absolute, within 24 hours or even a bit more I seem to remember was ok - 16 hours isn't really possible unless the blood is taken at the end of the day and gets to London by 9am. My surgery does blood tests first thing in the morning and wouldn't change the time for me.

Yes, I noticed a big change from the injections with many symptoms - one is that I feel much calmer and more "like myself" if that makes sense, and hardly any "brain fog". Pins and needles etc improved, tinnitus much improved. But I still have weekly migraines. And I'm still very, very tired - hoping this is part of a healing/repair process (ever optimistic!).


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