B12 injection

[chocaholic38]

Just wondering if any nurses around?

GP finally agreed to give me b12 loading injections, but after giving me the first injection the nurse immediately took bloods. My levels of b12 were borderline in October (224) which she had wanted to check if they had come down between then and January.. so when I went for my 3rd injection the GP said no as my level had came back at over 2000.
I tried to explain that she had taken the blood straight after injection but she was adamant that wouldn't have mattered. There's no way they jumped from 224-over 2000 in 3 months.
So can anyone tell me if she is right? I don't think she is. But now my injections have been stopped.

Thanks

This is a common problem. Having your blood taken during loading doses is inaccurate as the b12 is circulating your blood and falsely elevates your reading. This is within 3 months I believe of taking any form of B12, possibly 4. I can’t remember exactly. What actually matters is the b12 in your cells.

they need to test ACTIVE B12, which is more expensive, not serum B12.

I hadn't had any b12 supplements before the first injection, as I knew that they can affect the serum test result.
But the GP is adamant it wouldn't have entered the bloodstream within 5 mins, so wouldn't have affected the blood test taken.

I previously had an active b12 test done privately but my GP wouldn't accept it , and she said they don't do the active test on the nhs. Tried to get her to do an MMA test also but the lab rejected that.

Mine advised that they would do another blood test 3 months after loading to give things time to settle and get an accurate reading. It does seem very odd to test straight away.

honestly seems like commonsense is lacking these days

this happened to me, was on the injections for years, was told for life but a new GP tested my bloods, said it was high and stopped the injections

My understanding is that the NICE guidelines say not to test once you’ve had injections because the results will be unreliable.

I suppose the crux of the argument is the GP saying it wouldn’t affect results instantly, in the same appointment.

But you’re right, logically I can’t see how it’s jumped up ten fold. If it had come back at say 3/4/500 then maybe there’s an argument for the first result being slightly low and it increased on its own… but 2000..?

I think you’re just going to have to argue that the results aren’t valid as you were tested against nice guidelines. Unless you’re able to find some research/study showing how quickly injections circulate in the blood.

it must be very frustrating for you. I hope you get it sorted.

It is so frustrating. I had to quote NICE guidelines in order for them to trial the loading doses.
I'm back in a few weeks to get repeat bloods, but I have obviously had the 2 injections so not sure my levels will still be high. My level being 224 and the range is (197-779) she didn't think b12 is the issue.
She was very sure the injection didn't affect the result but then later said she really wanted the bloods done before the injection.. it feels like she was trying to cover up the nurses mistake.