Neurologist says there is no scientif... - Pernicious Anaemi...

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Neurologist says there is no scientific reason to inject more frequently


Many of you know that a few of my symptoms started returning about 5-6 weeks into injection treatment. I saw my Neuro today and I asked why I can’t change my injections back to weekly instead of monthly (I had 7 loading doses plus weekly for 4 weeks) and she had a very good response that made sense. She said that my levels will likely show sufficient b12 from being on weekly injections (fair statement) and that the reason I am feeling some symptoms return is that because nerves were affected during the deficiency and that you can have relapses of symptoms for some time (Seth12345 has said about the “roller coaster” with symptoms coming and going and others said it’s like “waking up” the nerves) and she said there’s no reason to inject when levels are normal or likely above normal (same with MMA - they should be lower with injections) because there’s no reason to do so, and that what I’m feeling is “flare up” pain because my body has produced these pains (neuropathy) before and the nerves are still very sensitive and can “fire” here and there. I told her about this forum and how people say that their symptoms get better with self injecting more often than the regular schedule and she said that symptoms can come and go and get worse or better all while healing but she kept referring to if you have normal levels FROM the injections, she can’t advise overloading because it would add no benefit.

I also have a script called gabapentin (pain medication for nerve pain)that she gave me back when I was first diagnosed and she said to take that as needed to manage the pain (My pain isn’t really that bad so I won’t) and that the reason they prescribe this is to get you through the bouts and flare ups that can come and go. She did offer to test my b12 and MMA right before the next dose, which is monthly, (so I’ll be 4 weeks from the last injection) and that if I am low, she would then prescribe a different regimen.

What she said really made sense but I know a lot of you feel that self injecting is helping. And if so, that is great. But I have trusted this Neuro for a while now and her medical reasoning sounds good to me, plus I have a remedy if the pain does get worse from the flare ups, but I just wanted to share this as informational.

40 Replies
clivealiveForum Support

Hi HopetoB12better I guess your neurologist is not speaking from practical experience.

I wish you well

We shall see 😃

And thx for the well wishes. Same to you! ❤️

I’m afraid that unfortunately, and sadly , your neurologist is mistaken , and P.A. patients on this forum know that all too well , to their cost . . Also testing B12 levels after injections have begun is a complete waste of time . They will be high., which only means that the B12 is floating round in the blood, but not that it is getting to where it is needed, into the cells of the body . Very best wishes anyhow!

Hi Wedgwood and Howto, sorry to but in on Howtos post.

If the B12 is floating around in the bloodstream after injections, how do we know if it is or isnt reaching where it has to go?

Is it just by following symptoms?

I was 209 in a b12 blood test 3 years ago and since took large daily doses of sublingual and it rose to 507. Does the same logic follow?

And if it does, how does it fit with the personal experience and knowledge that many on here state that sublingual dosnt get through the membrane in the mouth and hit the bloodstream?

I hope this makes sense and apologies if I have asked this before on a roundabout way. My memory is a little tricky sometimes 🤔

Thank you

Jane 😊

I really do not know why sublingual seems to work for some P.A. patients ( “work” meaning getting rid of the many and varied symptoms that are caused by Pernicious Anaemia ) I have a diagnosis of P.A. , and I took massive doses of sublingual B12 over many many months ,which had no effect at all ,and I became more and more unwell . I was truly desperate when I found the P.A.S, and this forum ,and found that I could self-inject b12 . That saved me . Improvement started immediately!

Yes , if you take sublingual B12 ,and the levels go up , but your symptoms persist , it’s obviously not getting to the cells . Or , if you have been B12 deficient for a long time, you may well have irreversible damage . .

But it is worth carrying on with frequent injections , because we hear on this forum from P.A. patients who have taken several years to recover.

Interesting ...

So is this to do with b12 molecules not getting , (supposedly) through the membrane in the mouth because they are too big?

I will be carrying on with my weekly SI, life us too short to take risks!

Thanks for getting back.


Well sub lingual never helped me , but some B12 deficient patients say that they are helped by them . Yes the b12 molecule is large , too large some scientists say, to get through that sub-lingual skin.

But also , it seems that even if one does get plenty of B12 into the blood, it’s not necessarily finding its way into the cells where it’s needed in order to make the myelin sheathe which surrounds the nerves. That’s why we are told that testing for blood levels of B12 is a useless exercise.—Those levels will always be high , when one is receiving injections . It seems that only when the B12 reaches a certain level , that it does enter the cells . And that level varies substantially from PA patient to P.A.patient. Hence the different regularity of B12 injections that are required . I’m sure I’ve not explained that very clearly .

The whole question of treating P.A. is difficult and many doctors don’t have a clue . It needs loads of research . It’s one of those “Cinderella” conditions . Heaven help us all . ( but thank goodness for this forum ! )


Yes definately! Thank goodness for this forum.... I am learning so much that I would never have known. And as a result I will be healthier, I'm sure.

You have explained it very well Wedgewood, thank you so much.

Its interesting that you say when the B12 injections are more frequent and the levels are higher that it does start to enter the cells. I am switching back to every other day to SI from trying weekly.

Still pretty much bed bound after 6 or so weeks of injections.

However I can feel my head 'waking up' if you can understand that? And other symptoms such as leg cramp seem to have stopped.

It's the CF and restless legs that is still always me.

I am hopefull though going forward.

Thanks again for your responses and knowledge.


Yes, the B12 can start to enter if the levels are raised by more frequent injections. I was injecting more and more regularly , and still no effect on my symptoms. It all started to happen when I injected weekly . But it is different for everyone. My P.A. neighbour has an injection every 12 weeks , and that’s sufficient. . Another P. A. friend injects twice daily to keep well . Opposite ends of the spectrum .And there’s everything in between ! -That’s P.A. ! Might have to do with genetics or how long one has been deficient. Who knows ?

Hmmnn ....I may try the twice daily for a week or so and see if it is more effective.

Thanks for that


Thanks for making the point about the cells. I have another appt with a different Neuro to get another opinion and I will ask about this!!

I honestly wish you the very very best .🍀🍀🍀👍👍👍

Bonkers - take Gabapentin with known side effects and toxic at high levels to partially mask the problem, rather than totally safe B12 jabs which will actually fix the problem...

That's why I self inject.

Good luck!

Agree with you 100% . But the neurologist will keep him/ herself in work with this idea !

I couldn't live without my gabapentin. The side effects are as nothing compared to the feeling of walking on broken glass and having evil goblins stick red hot needles into my toes when I'm trying to sleep.

Some people will have such severe nerve damage that it will never be repaired, no matter how much B12 they take.

I do find great relief with gabapentin but I do hate to rely on it for just relieving symptoms.

Seth12345 in reply to fbirder

I second that on gabapentin... When that nerve pain kicks in you need something... And for anyone that's experienced the severe nerve pain they know exactly what I'm talking about!

I also found that doing more injections sometimes exacerbated the nerve pain... That was one of the reasons I relax my injections to once every week and a half at this point. If I do twice weekly injections I tend to have bouts of horrible nerve pain.

I get what you are saying. I am having my blood tested in 2 weeks to see if any of the last injection stays. Ugh. This is awful 😢

I hope you can find a positive, long term solution to your problems.

If it's any consolation, lots of us with enough B12 and supporting supplements do get reasonably well.

I won't be able to sustain it long term but my current job for the next few weeks until harvest gets underway is driving from farm to farm pressure wash cleaning grainstores - going up super high ladders, out on walkways above grain bins, in silos and all sorts of things! OK, I'm shattered when I get in but I am doing it!

Today is my 5th anniversary of every day injections and I have got to this point from barely being able to walk or talk, with no memory!

So keep trying - you can get there!


your neurologist does sound reasonable. Checking the MMA and homocysteine before your next jab is a good precaution to look at whether you have a functional deficiency (though it is only looking at two of the many processes that go on in cells that use B12 - so may not necessarily tell the whole story but its also difficult to find ways of measuring most of the other processes), and you are by the sound of it still looking at monthly injections when it was 5-6 weeks that was causing return. Checking B12 to see if it is low is a good recognition that not everyone retains B12 from injections in the same way.

Personally I didn't get on with gabapentin - took one tablet and it made me feel so ill that I never touched it again. I do find a chilli topical gel does help with symptoms of carpal tunnel though that isn't totally B12 but it does show that there are definitely options.

Hope it all goes well

Yrs I've been told similar. of course you have to trust the specialist.

You also have to follow your body and try and make Informed choices.

I've been told 3 very different things by 3 neurologists.

I think bits of each are proving to be right.

The last consultation was with a neurologist that injects b12 6 weekly.

He said to keep the b12 levels high and stick to the regime that you feel helps you. Also more research is needed. He was the one that wrote to the go to ' sanction SC at home.

An other said b12 poisonous in higher amounts and I was addicted.

Another said stick to the bnf guidelines and handed over to Gp.

You just have ti work with what makes sense to you.

I dont think relying on bloods to change regime is sensible though.

Go by your symptoms.

Take care

I like the phase 'flare up' because that describes the pain which comes on and off with my legs/feet.

has anyone tried CBD balm to help with the pain?

Seth12345 in reply to jillc39

I tried CBD many times and it didn't help me. It calmed me a bit and helped me fall asleep but the pain went right through it.

fbirder in reply to jillc39

I've tried CBD jellies, sublingual oil, and vaping. All at the highest doses available. I even boosted the top-dose oil with CBD solid.

They did nothing.

Ah .. didn't know that🤔

Do you know which tests Fantic?

Thanks for responding.


What other tests?

There is a test to find out how much b12 you are absorbing but it’s a costly thing and not many people are put forward for it. I can’t remember what the test is called it’s bugging me, my hazy brain.

I just self inject and if my docs decided no more I’ll still inject my self. You know your own body and how it feels if they help take it, it’s your quality of life no one else’s We battle every day

CherylclaireForum Support

May be a good idea to have MMA tested if offered - even after starting treatment.

MMA level is supposed to go up when B12 deficient because the two join together at some point in the B12 journey and become something else (this is not a scientific explanation !)- so if there is inadequate amounts of B12 to meet up with the methylmalonic acid, it will build up in the boodstream and continue rising. Once adequate B12 treatment is given, MMA should soon return to normal level. So 2-3 days after loading injections are completed, you would expect to be back within range.

Mine, although not tested until later on, took 3 years, despite frequent B12 injections, to get back down into range. It was tested 6 times in all. No reason was found although DNA was checked.

There is also current research (see Pernicious Anaemia Society newsletters on website) looking into the reason why some people need more injections than others. The trials proved that a study of stool samples demonstrated a remarkably clear difference between the two groups.

The Adult Inherited Metabolic Diseases consultant who gave me my DNA results knew about the Pernicious Anaemia Society, about Martyn Hooper and about the new research and the trial findings. Hopefully this research will continue- and eventually results published, a new test established and treatment patterns altered accordingly.

Until that time, you might want to see what your MMA is up to. Doubt that your B12 will be below range after a month. Who knows? As you can see, we are all different !

Let us know.

I am afraid my husband says that the MMA test is only a marker for helping diagnose B12 deficiency. Like all the B12 serum tests it is affected by supplements and injections for months. They also do not correlate at all well with symptoms. The sensitivity of the MMA test has not been fully tested and defined. There is evidence that it's sensitivity is poor. In particular patients who have had bariatric surgery and therefore cannot absorb B12 from their gut have their MMA return to normal with a minimal dose of B12 that does not help their B12 deficiency symptoms at all.

CherylclaireForum Support in reply to Retteacher

Yes, as a secondary marker for B12 deficiency, a confirmation, MMA is useful once other possible diagnoses are ruled out - renal problems (blood test) or SIBO (hydrogen breath test)can also be indicated.

This makes it a useful tool for evaluating success of the B12 treatment administered if there is some doubt over response.

If MMA remains raised after low serum B12 is treated with B12 injections, having ruled out the above, this introduces the possibility that the loading frequency should continue.

NOTE: Recent treatment with antibiotics can give a false normal MMA reading.

The most common problem with MMA testing appears to be related to varying reference values between laboratories -

but "the most widely-used value is 270 nmol/L" (Stichting B12 Tekort- who recommend treatment for those with values in the grey area with distinct B12 problems).

The Mayo clinic credit "moderately elevated values" as a B12 deficiency indicator, and "markedly elevated" MMA values as probably indicating methylmalonic acidemia (usually diagnosed at birth). However their upper range limit is quite high at 400 nmol/L.

Standard values for plasma MMA are below 271 nmol/L, agrees laboratory Professor Obeid of Hamburg (in Dialog 2014/1), who acknowledges higher limits set in various studies would make 271-450 nmol/L somewhat of a grey area - which "even so, should be reduced by supplementation".

He expects MMA concentration to "decrease approximately 1-2 weeks after initiation of vitamin B12 supplementation , depending on the dosage and the initial MMA concentration."

So if MMA found to be still raised despite B12 treatment, renal problems and SIBO having been ruled out, we are left with evidence of some internal failure to respond normally to the B12 injections already administered. Or else perhaps that methylmalonic acid levels were previously very high and are dropping - which we can't know restrospectively, and would require regular testing to monitor for any continued reduction. The opportunity to discover "the initial MMA concentration" level in most cases would have of course long since passed by this stage.

Which just leaves "dosage".

Surely, the important point is that if a small dose of B12 returns the MMA to 'normal' at a dosage that has no effect on the patients symptoms, it cannot and should not be used to test if B12 injections or large oral doses are working. It shows that the MMA test is very insensitive as a means of showing treatment is working. One of the main reasons for this is because in patients where the B12 deficiency symptoms are primarily neurological, there may be a problem in getting the cobalamin from the blood into the central nervous system without very large serum B12 levels produced by frequent injections.. Modern doctors are spuriously obsessed with 'normal' laboratory ranges without acknowledging that the 'normal' range for a patient to function properly with a B12 deficiency malfunction may be quite different from that of unaffected healthy subjects. Another example is the tendency to believe that returning hypothyroid patients TSH values to the normal range means that their levothyroxine medication levels are correct. There is a tsunami of patient complaints across the world because many doctors now work to this false dogma, ignoring the patients unresolved or increasing symptoms. My husband deplores this blinkered laboratory approach which goes hand in hand with a failure to respond properly to the frequent need for an holistic approach to a patients multifaceted problems and symptoms. Of course if a patients problems are caused solely by a misguided inadequate diet then limited supplementation may be adequate to resolve symptoms and return serum levels to the laboratory normal range. Sadly this is often not the case in B12 deficiency patients which is why the 'British' guidelines advise against retesting serum levels once injections have commenced, you just get confusing and potentially misleading results. Doctors need to treat the symptoms not lab test results.

Thank you 😊

NICE say that B12 should be injected IM every other day for as long as needed until no further improvement. Your neurologist is not following these NHS guidelines that would not have been set unless they had been shown to work.

What is the NICE and NHS guidelines that you are referring to? Is this in the US?

CherylclaireForum Support in reply to Bellabab

True. Good point.

This, by the way, is also the frequency for B12 injections recommended for those who do prove, by DNA testing, to have a genetic inability to process B12 at cell level . The Adult Inherited Metabolic Diseases consultant who told me this said that even after this diagnosis and treatment regime is included in the feedback report, some GPs will refuse to treat the patient at this frequency !

Maybe my Neuro is only giving me the standard dose because my bloodwork (after loading doses) improved? My b12 and MMA were both right where they should be after about 10 days of injections. I know there is a concern that they may not stay that way, but the initial therapy worked so I guess I will just continue with the recommendation of Cleveland clinic.

CherylclaireForum Support in reply to HopetoB12better

Good to hear you are doing well so far. Keep an eye on symptoms, okay ?

Thanks Bellabab. I just looked it up and it says it’s did the UK. I’m in the US so that’s what I didn’t know what it was. I will look at the NICE info. Thanks again 😊

Bear in mind, a hundred years ago, there was no scientific reason to inject at all.

OK, so there wasn't any B12 available for injection. :-) But if there had been (let us suggest someone squeezed and filtered animal liver), there would still have been no scientific basis for injecting it.

However, someone regularly injecting it would have been treating their Pernicious Anaemia effectively. Science oftens comes after the empirical approach.

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