If I got an active b12 test done privately and it showed I was deficient, would my GP give me injections?

So I'm thinking of getting an active b12 test done privately because I'm not getting anywhere with the NHS. I've now had 3 b12 tests in the last 9 months with an endocrinologist and they haven't tested me for pernicious anemia or done any other tests reagrding b12, they just keep saying test it again. My results have been:

163 (150-900)

148 (150-900)

226 (180-1000)

My GP said that non of these results would require any attention as they are not low enough. Private testing will cost me £112 so I don't want to get the result back saying its deficient and my GP telling me that they won't give injections based on private testing or something like that. Has anyone had any experience in dealing with this problem? Will the GP seriously consider the active b12 test?


15 Replies

  • Hi Carly,

    No GP can deny patient treatment if theye come up with a private test showing deficiency, they can possibly insist on re testing, but that is all. You can also refer to the new BSCH (British Society for Haematology) guidelines on B12 and folate def (if you are in UK) that clearly mentions treatment should not be delayed if symptoms are obvious, see:


    "Summary of key recommendations

     The clinical picture is the most important factor in assessing the significance of test results assessing cobalamin status since there is no ‘gold standard’ test to define deficiency.

     Serum cobalamin remains the first line test currently, with additional second line plasma methylmalonic acid to help clarify uncertainties of underlying biochemical/functional deficiencies. Serum holotranscobalamin has the potential as a first line test, but an indeterminate ‘grey area’ may still exist. Plasma homocysteine may be helpful as a second line test, but is less specific than methylmalonic acid. The availability of these second-line tests is currently limited.

     Definitive cut-off points to define clinical and subclinical deficiency states are not possible, given the variety of methodologies used and technical issues, and local reference ranges should be established.

     In the presence of discordance between the test result and strong clinical features of deficiency, treatment should not be delayed to avoid neurological impairment.

     Treatment of cobalamin deficiency is recommended in line with the British National Formulary. Oral therapy may be suitable and acceptable provided appropriate doses are taken and compliance is not an issue.

     Serum folate offers equivalent diagnostic capability to red cell folate and is the first line test of choice to assess folate status.


    If your GP does not see any reason to treat you then ask for a referral; top a haematologist. Then request further testing as your serum B12 levels are on the low side of normal, can dip under and you have symptoms.

    My Daughter wanted to get off B12 treatment as she and her GP thought her B12 deficiency was perhaps sorted after 3 years of standard treatment. She got one infection after the other, became very scatty, car bumps etc, so after 6 months of no B12, I offered to pay for active B12 test in London, GP agreed, results Active B12test, 28 pmol/L (lab range 35 - 141), Active B12 concentrations under 25 pmol/L suggests B12 def, vitamin B12 can not be excluded if Active B12 (holo TC) concentration is inbetween 25-35pmol/L, because of her result her blood sample was referred for mathylmalonic acid (MMA) analysis, her MMA was 433 nmol/L (ref range 73 - 271), MMA was above the upperlimit, which meant functional vitamin B12 def at tissue level. Her GP got the results ( and an offer to ring and have more explained if needed) and put her straight back onto B12 injections and she knows now its for life. You only need to look up what high MMA does to a body to know that is not good for a body.

    I hope this helps,

    Kind regards,


  • Thanks Marre I think I'll just have to get the private test done

  • I was taking B12 supplements and iron tablets when I had the Active B12 taken. Can supplements affect the result? Does iron tablets mask any other results?

  • B12 supplements will impact on active B12 result so people here say to stop them for at least couple months before test. Don't know about other one. Sorry

  • I my opinion it is utterly ridiculous that your GP cannot see how low you are in the test ranges anyway!

    How low does he think you need to be...!? What does he think the ranges are FOR?!

    Can you see a different GP?

    I know it sounds like a silly question, but have you tried supplementing with B12 yourself to see if you see an improvement? I think some people use drops.... (I'm sure a B12 person will correct me if I'm wrong here....) :)

    It might be easier to convince them if you can prove that your symptoms and/or test results improve....


    (Visiting from Thyroid UK) :) xxx

  • Thanks for the reply :) I know its just so frustrating at the moment, I've seen 2 different GP's and they keep saying its not low enough. The problem I have is that I'm having a lot of medical investigations at the moment for my symptoms and the b12 deficiency is the only thing thats really coming up at the moment so I don't think supplementing now without having more tests done is a good idea yet :/

  • Surely 148 is below the normal range anyway? I'm pretty certain I was 147 when I was diagnosed and was immediately referred to a haematologist.

  • It was below the range but they decided to send me to a gastroenterologist for slight malabsorption instead (because folate was on the low side and I had a borderline vitD) and when he tested me it had gone back up again so they refused to keep on testing and have delayed all tests and treatment for 6 months.

  • Aargh. That's not very helpful...

  • Recently diagnosed here. My level is 140 and considered just below lowest level of 150. Reading around you will find the range varies from place to place! I am on B12 jabs every 3 months - no loading doses as no other symptoms. However I am considering using patches as I believe I don't have the energy I once had..................

  • Thanks for the reply, how many b12 tests did you have to do before you were diagnosed? They haven't even bothered running a pernicious anemia test on me yet :/

  • I might be in the same boat as you op, especially if the Dr doesn't think anything is wrong next week.

    Do you mind telling me which private lab you'll be using?

  • Hi BrecklandRanger ,

    Just in case you get no answer. You will find some info in this post of where others had private tests done; see:


    Kind regards,


  • Hi BrecklandRanger, I was actually quite surprised how many places do this. I just rang my local private hospital and asked the receptionist if they do it and she said yes. Apparently you just go to your GP and ask for a blood test referral form and then take that form and go to the walk in centre anytime between 9am-5pm and pay and get the blood taken. It may be a slightly different procedure for you but it seems quite straight forward. I think this private hospital is owned by BMI Healthcare

  • Thanks. I'll probably use the BlueHorizon labs (also recommended by the Thyroid group here), as they're cheaper (about £80).

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