Following on from previous post.
Medichecks said my B12 had dropped -
49.6 pmol/L (37.5 - 150)
So I took a test with Superdrug and the results are -
142 pmol/L (25.1 - 165)
Help lol which is correct. I stopped my B complex which contains Biotin 2 weeks before both tests.
Your GP should check that you do not have Pernicious Anaemia. If you did have P.A. you would have to have regular B12 injections.
I didn't know Superdrug did tests, I know they offer phlebotomy. Which lab did Superdrug send the test to and which lab did Medichecks send their test to (it would be Inuvi or County Pathology).
Was the reply from the PA forum not helpful?
onlinedoctor.superdrug.com/...
I didn't know about this service either but it's a bit pricey and not the best...
£60 for Thyroid £38.99 for B12
Ah, so they use TDL. Medichecks used to use them occasionally.
So could the superdrug one be not reliable then? Sorry no idea about labs etc
So could the superdrug one be not reliable then?
No, I wouldn't say that. I've had a couple of my tests processed by TDL, quite some time ago, and didn't find a problem.
I think it's best to stick to just one lab, different machines calibrated differently, different ranges, all means you can't compare results from different labs with any accuracy.
If the Superdrug test was after the Medichecks 49.6 result I'd be questioning why, after the previous tests show your B12 falling, has it suddenly shot up so much, unless of course you started injecting or started taking very high dose B12 supplements.
The superdrug test was a week later and not started taking any B supplements or injections. I used superdrug as it said could get B12 injections through them if showed a problem but it said a figure much higher than I've ever tested before.
In that case I'd be contacting Superdrug, give all previous results/date/labs, etc, and ask if they can explain it.
I have sent superdrug a message back on the results.Will update if I get a reply.
I have used medichecks and they test for active b12 NOT serum b12, active b12 is the amount of b12 thats available for your body to use. I thought you had to be free of any b12 supplements or in foods for 4 months to get an accurate test. B12 serum can be high but unuseable by the body ,that may be the difference between the tests you've had
I couldn't see where they clarify whether they test for total or active but assume by the range it is active?? 🤷♀️
Charlie27612
I thought you had to be free of any b12 supplements or in foods for 4 months to get an accurate test.
That is if you want to know what your body is holding on to, to get a baseline. If you want to know what your supplement is achieving then you continue supplementing.
B12 serum can be high but unuseable by the body ,that may be the difference between the tests you've had
All the OP's tests are Active B12, you can tell by the ranges, Active B12 tests will have a narrow range, eg
Medichecks processed by County Pathology -37.5-188
Medichecks processed by Inuvi - 25.1-165
The Doctor's Laboratory (TDL) - 25.1-165
Serum (Total) B12 has much wider range, eg
Blue Horizon processed by County Pathology - 145-569 pmol/L
Blue Horizon processed by TDL back in 2018 - 197-771 pg/ml
My GP surgery - 150-900 ng/L
Medichecks Results
No response from superdrug yet.Monitor my health results -
ACTIVE B12
17/07/2023
54 pmol/L
Normal
FOLATE
17/07/2023
3.3 ug/L
Normal
Blood results
Latest results 
B12 supplementation query
T3 re-test results 
