I had 6 loading doses of B12 in September following a B12 level of <145 (test doesn’t specify below that cut off) I had some symptoms including muscle aches particularly my legs above my knees, anxiety, panic attacks, fatigue, dizziness and pins and needles on my left hand. No evidence of anaemia on blood results. No IF antibody but positive for Gastric Parietal Cell antibodies. All of the symptoms improved by a month or so post loading doses. In November Dr re tested B12 level. It was 720ng/L
Dr was reluctant to prescribe the 3 monthly maintenance injections. Wanted to wait 6 months from loading dose. I pushed for a January test. Results are back and B12 has dropped down to 305ng/L. I’ve noticed the muscle aches creeping back in and the tiredness the last week or so.
I know 305 is within ‘normal’ range (as is noted on the results shared on my NHS app) but I’m wondering if it normal to drop that significantly if there isn’t an absorption problem that would warrant maintenance injections…
Can anyone share their thoughts?
Thank you!
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Sparkleros
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I'm assuming you're in UK. Let me know if you're not.
You list dizziness and pins and needles among your symptoms.
These are neurological symptoms.
My understanding is that UK people with B12 deficiency with neuro symptoms present should be on the following treatment pattern....
A B12 loading injection every other day for as long as symptoms continue to get better then a B12 maintenance jab every 2 months.
There is no set limit for how long the every other day loading injections can continue for, could be weeks or even months of them.
Your GP appears to have put you on a treatment pattern for those without any neuro symptoms.
Your GP needs to look in Chapter 9 Section 1.2 of their BNF (British National Formulary) book or at online BNF. See section on Indications and Doses in link below.
Search online for this UK document "NICE CKS Anaemia - B12 and Folate deficiency" and look in Management section which discusses treatment patterns for B12 deficiency. If you have enough time, read the whole document.
Also try to find the local B12 deficiency guideline used by your ICB (Integrated Care Board) in England or Health Board in Wales/Scotland. These local guidelines can vary from what NICE document says.
Search online or search forum posts here or submit a FOI (Freedom of Information) request to ICB/Health Board asking which B12 deficiency guidelines they are using and for a link to or copy of them.
There may also be useful information in ICB/Health Board guidelines on Macrocytic Anaemia.
This is a type of anaemia where red blood cells are larger than normal and it can be associated with B12 deficiency and folate deficiency.
Some ICB and health board B12 deficiency guidelines are not as helpful as they should be. See blog post below....I hope you are not in this area.
It's vital to get adequate treatment. Delayed or inadequate treatment can increase the risk of developing permanent neurological damage. In severe cases the spinal cord can be affected.
If GP is reluctant to put you on treatment pattern for those with neuro symptoms, might be worth showing them this article below.
PAS article about SACD, sub acute combined degeneration of the spinal cord
I don't know the answer to your question, how fast serum values drop after injection, but to me it seems strange to wait until levels drop towards the bottom of the reference range before approving the next injection. It would seem better to at the very least try to keep values around and above the mean. Because why should a person with a history of B12 deficiency and probable absorption problem be kept only just above the bottom of range? I. e. lower than average.
This all seems to be heading in the wrong direction :
To my mind, the GP should be wondering why your B12 was below 145 (ng/L or pmol/L ?) in September. Assuming non-dietary cause (?), then an IFab test (Intrinsic Factor antibody test) might show a positive result - but only returns a positive result for 40-60% of those with PA (pernicious anaemia). So NOT a definitive pernicious anaemia test as such, as you might have to have more than just the one test. This would rely on your GP understanding that this is the case. A positive result is almost a certainty for PA (95% ).
"No evidence of anaemia on blood test results" - that cannot rule out PA as the problem. There are a few types of anaemia, but if by this you mean "no evidence of enlarged red blood cells" (macrocytosis) - yes, that would indicate PA, but again, is only found in about 60% of cases.
"Positive for Gastric Parietal cell antibodies" - the BCSH (Haematology) believe this test to be positive in 80% of those with PA but also in 10% of "normal" individuals. They believe that a positive here can later lead to PA, but do not recommend this test is used to determine PA status.
Not easy to get an answer, is it ?
So there is no reason that I can see here for a GP to be reluctant to start a maintenance dose particularly after a successful loading dose. I say "successful" because of early alleviation of symptoms, not because your serum B12 has tested particularly high after the loading dose, or that you are retaining the loading injections well ....
I suppose the most useful question is "Are you even at a stage that you would wish to maintain yet ?" - because Sleepybunny is absolutely right: you are not being treated correctly for a patient presenting with B12 deficiency symptoms that include neurological symptoms. You aren't being treated correctly anyway.
If your GP waited six months (whether from your loading dose completion/ from your November test), s/he would see what is already evident: your B12 is dropping. It would, in six months, doubtless have dropped further. By which point, you'd need to start again with those loading injections.
Now why would a doctor want to do that to a patient ? It's nonsensical.
In fact, why would a doctor want to test serum B12 twice, after starting B12 injections, against all the medical advice given in UK guidelines (NICE, BCSH, BNF) ?
There is a reason why your B12 serum levels dropped initially. That reason has not yet been found.
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