Safe to carry on alternate day inject... - Pernicious Anaemi...

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Safe to carry on alternate day injections


Hi all I had low folate a few weeks back and was taking folic acid but I did not get on with it as it made me feel sick and gave me gastric distress. I’m now completely off it pending another blood test next week to see where things now lie.

Is it safe to carry on alternate daily B12 injections still during this time? Also if folate comes back low is it still safe to carry on whilst I work out what to do about it? Thanks.

36 Replies
clivealiveForum Support

Hi EmilyCJ what strength folic acid were you taking?

I'm not medically trained.

EmilyCJ in reply to clivealive

It was 5mg but I was borderline low. Think GP wants to see if I can get away with a smaller dosage.

clivealiveForum Support in reply to EmilyCJ

5mg is a large dose.

Personally I have taken 1 – Folic Acid 400μg tablet every day for more years than I can remember. These can be bought cheaply from any pharmacy or local supermarket.

You cannot "overdose" on B12 as any excess to requirement is excreted via your urine.

I am not a medically trained person but I've had Pernicious Anaemia (one of many causes of B12 deficiency) for more than 46 years.

I wish you well.

There is no problem taking any amount of B12 if you're deficient in folate. You may read some people saying that injecting B12 increases the body's need for folate. That is wrong.

I would try 400 mcg of folic acid a day. If that doesn't work then try boosting the amount of natural folate you consume. Leafy green veg, pulses, legumes, fortified breakfast cereals. However, bear in mind that the folate in food isn't as well absorbed as that in pills, so you may need more than what is written in the ingredients.

EmilyCJ in reply to fbirder

Thanks that really helps! I’ve had a lot of people telling me I cannot take any B12 without folate as it won’t work.

Also that I’ll be placing a large demand on my folate levels by keeping up with my alternate day B12 injections and cause myself further problems.

Must say it’s scared me to death and left me very confused by the whole thing. I didn’t know anything about folate when I first got diagnosed with PA years ago.

The test is being done next week and I haven’t tried a small dose so I suppose I’ll see what my level is saying.

fbirder in reply to EmilyCJ

It is very annoying that people will spread such nonsense.

When we inject B12 frequently we are keeping our B12 levels topped up to the maximum. Suggesting that this will increase the body's need for folate is as daft as suggesting that keeping your car's fuel level close to maximum will increase the amount of oil that the engine will need.

There can be a problem the other way around - taking folic acid with low B12. The main problem is that it can make a B12 deficiency harder to diagnose, but that's irrelevant if you've already been diagnosed. There is also the possibility that it can lead to large amounts of methylfolate in the body. It's not sure if this may, or may not, be harmful.

But taking large amounts of B12 with low folate is no worse than having normal amounts of B12 with low folate.

EmilyCJ in reply to fbirder

Thank you! So that means my B12 will still work like it’s supposed to regardless is that correct?

A few people have now said to me without me taking the folate I will simply “pee all the B12 out” so I may as well just stop doing it.

That worried me a lot as I’ve been doing really well with the frequent injections.

I will increase foods, get the folate test done again and try the smaller dose.

fbirder in reply to EmilyCJ

Yes, your B12 will work as long as there's enough folate. If there isn't enough folate then the amount of B12 will make no difference at all.

The amount of folate has absolutely zero effect on how much B12 gets peed out.

It can be good fun trying to find new and interesting dishes that have a lot of folate. I'm fond of throwing a handful of spinach into stews and curries at the last minute.

EmilyCJ in reply to fbirder

Thank you I think that clears it up.

I’ll look into my diet and how I can get more and wait for the blood test results. Could be I am stressing about nothing and a simple low dose supplement will suit.

Cells need vitamin B12 to use folic acid and when vitamin B12 levels are too low, folic acid cannot be used and builds up in the blood, so B12 levels must be given a chance to build up before supplementing folic acid.

fbirder in reply to Polaris

Cells need vitamin B12 to use methylfolate. In the absence of sufficient B12 the body has no other way of converting methylfolate into folate. That means that all the folate in the body ends up stuck as methylfolate.

The problem is that methylfolate is just one form of folate. Other forms (methylene tetrahydrofolate and formyl tetrahydrofolate) are important in other biochemical processes to do with the synthesis of three of the four bases in DNA. If all the folate is trapped as methylfolate then those other forms aren't available and those other processes cannot be carried out. Having an inefficient DNA production mechanism is never a good thing.

Taking folate (either as supplements or in food) replenishes the supply of those other folates, allowing those other processes to happen. This is a good thing - until the levels of methylfolate build up to unwanted levels. Nobody is quite sure how high that might be.

But, as you say, if this methyl trap is happening then blood levels of folate will rise as it all gets stuck as methylfolate. If, as in EmilyCJ's case, blood folate is low then B12 levels aren't low enough to stop the conversion of methylfolate.

Yes, definitely keep going with the B12. Polaris has it the right way round!

As fbirder has said in previous replies to other posts, the processes that use B12 need a form of folate (vitamin B9) to work, but getting your B12 first is more important.

You may well be able to get enough folate from your diet but if you can't then you will get a return of your B12d symptoms and folate deficiency symptoms, which are very similar. It would be good to Google this so you know what you are dealing with.

If you can't get enough from your diet you can try taking the 400 mcg tablets (they are cheaply available in supermarkets) either singly (or in multiples if you need more) with food. If I take them on their own they make me feel really sick but they are OK in small doses with food at each meal.

12 and a half of the 400 mcg ones is the same as one of the 5mg ones your Dr gave you.

If that doesn't work then you might do better with either methylfolate or folinic acid tablets, both of which suit some people and not others.

The folic acid tablets don't work for me but methylfolate ones are good and don't make me feel sick either but will give you a headache if you have more than you need. Folinic acid tablets are expensive but work for some where the other sorts of B9 don't suit.

Don't worry: you'll get there - good luck!

Thank you I am very stressed about it all. I used to take 400 methylfolate years ago as recommended by thyroid group. This was fine kept levels high and me ticking over. When I tried a Methyl B12 spray with Folate in not that long ago I got some really unpleasent side effects and after this I could no longer seem to tolerate any folate at all as it sets off a jittery/wired reaction despite having used the lower dose for many years prior. I was getting headaches but had no clue they were linked as I'd been having so many symptoms anyway.

I've since been too scared to try methyl anything again as this didn't happen that long ago and effect lasted a long time.

I've since read about methylation etc. and the effects are what I had jittery/insomnia/headaches basically like I'd had 1000 coffees and couldn't sit still. So I think methyl anything doesn't really suit me and cannot use it anymore.....

I stopped this then found I was becoming lower in folate levels. I then tried the folic acid from doctor and boom major stomach complaints. So I'm incredibly stuck. Think I need something to keep me ticking over as symptoms are stronger without anything but what to do if nothing suits? Would folinic have same effect as the methylfolate and make me go nuts again? I haven't tried low dose of folic only the strong stuff so don't know whether to give that a whirl first either.

I'm getting fed up of being complicated! Was feeling very well until I ruined myself with too much methyl - must admit had no idea about methylation or anything prior to this. Very worried I've screwed it all up.

fbirder in reply to EmilyCJ

Several people have reported the symptoms you describe with methylcobalamin. The one time I injected it I felt terrible. But I have no problems with 1000 mcg of methylfolate a day.

I would try the low dose folic acid. If that don't work then I'd give folinic acid a try.

I do feel for you - I've also accidentally done things at times which have screwed things up and it takes months to get back to a good level again but usually you can.

I think it's because anything unexpected can trigger an autoimmune response and it takes ages for it to settle down - as well as it taking a while for our levels of things to stabilise again.

If I was in your position I would increase my veg intake and get some 400 mcg folic acid tablets and try taking one with my main meal. It's a tiny amount and should be fine. I'd then try taking one either every day or every other day for a week or so to wait for any reactions to settle down and then review things. If I felt OK on that I might carry on or maybe try increasing the dose slightly and see how that goes.

I don't know about folinic acid but you could ask on the Facebook PA/B12 support group or try a specific post on here with that in the title. This group has a lot of very knowledgeable people who don't usually respond because they have been put off by demeaning and unhelpful responses but if you ask a specific question they may help you.

Yes I suppose I can even out in the end. Just struggling to know whether to add in the folic acid again lower dose or leave myself alone for a while and just put up with feeling crap!

I'd be inclined to try a low dose because you don't want your levels to continue to drop. If you can aim to stabilise it that will be a good first step. Then see if you can gently increase it in time.

Thank you. I will try out the folic again on Friday night as I have a week off work. Very confused about the whole thing. Had a wonderful week on the folic acid 5mg and thought Yay this is what I’ve been missing then stomach kicked in and all went wrong. Very confusing but perhaps starting off a lot lower would suit and was just a massive shock to the system.

I agree with you completely!

Good luck! x

Thank you very much for taking time to talk to me! I've been really anxious and worried about the whole thing. x

I don't blame you - when my body won't work or has a paddy or another thing breaks I also feel like it's the end and it's really scary! However I'm getting to the point where I've managed to pick it up and find someway around the problems so many times - with help from people here and on the Facebook group - that I keep reminding myself of this and hope I can just find yet another solution!!

The trouble is that when you feel bad you know time is gradually running out and you have to do something so no wonder it makes you anxious - and of course low B12 and B9 cause anxiety so the problems compound themselves, don't they! But at least you know this and know your response is logical and reasonable. xx

Yes definitely. The anxiety I’ve got now is dreadful as I feel very stuck with it all. I thought SI was going to save me and was feeling really well and now keep hitting all these road blocks! I thought getting over the self injection would be the biggest hurdle of all.....

You’re right family don’t understand at all and can’t see my panic about it but it really does end up feeling like you’re running against the clock to fix things or risk big damage. I think I will order some liquid folinic to have on hand if this folic acid low dose trial doesn’t work.

Excellent advice and support from deniseinmilden .

Not sure if this helps but several members of our family have Hashi's/B12def. with, I suspect, the MTHFR gene, and here are some notes I took from a Webinair given by Izabella Wentz, pharmacist and thyroid specialist:

Methylfolate best as, if you have MTHFR gene, folic acid is not well absorbed.

Ferritin - deficiency causes shortness of breath, insomnia - optimal range 90-110 no/ml

Vitamin D - for energy - optimal range 60-80

Zinc - optimal range 70-90 up - deficiency impairs wound healing.

Selenium - 200-400 mcg per day - reduces antibodies and anxiety.

Thiamine (vitamin B1) - fatigue support - 600 milligrams per day.

Important to improve gut health. Remove gluten and, if appropriate, dairy.

Eat more protein, limit carbs and increase good fat.

TESTS : TSH, FreeT3, Free T4, Thyroid Peroxidase antibodies (TPO), Thyroglobin antibodies (TG), Reverse T3

Good luck finding answers Emily.

EmilyCJ in reply to Polaris

Thank you I do have Hashis and have done lots of work on this across the years. Get regular labs and very settled on NDT. Don't eat gluten. Vitamin D and iron are completely fine. It's just this annoying folic/folate thing I'm really struggling with. Completely lost on it all. Don't have funds to get genes tested - not even sure what would do with the info as can't find a well versed doctor in it and no money to pay for one either. It's all a bit over my head whilst feeling so ill too.

All feeling a bit hopeless at the mo as feel like without some form of this I am going to get no better and get worse all over again. GP's no help. It's either take folic or don't from them. I'm seeing a haemotologist end of Jan but don't expect much help from them either as it's a complete lottery. Feeling very stuck indeed.

Polaris in reply to EmilyCJ

Hi Emily, yes I'd looked up your previous posts and noticed you had Hashimoto's too and also g/f and on NDT 🙂

Personally, I try to avoid synthetic folic acid (expert explains why in film about Sally Pacholok) and eat daily amounts of sauerkraut, parsley, dill, etc. as well as nuts (Brazils) for selenium.

FoggymeAdministrator in reply to Polaris

Just a word of caution here...this advice from Izabella Weinz is in relation to those with thyroid problems and may or may not be relevant to those with PA (or B12 deficiency from another cause).

In particular, there are contraindications related to taking selenium supplements, in particular...those with skin cancer (melanoma) or an increased risk of skin cancer should NOT take selinium.

More information, including potential drug interactions and further contraindications, can be found in this link:

More information about Thiamine supplements can be found here:


EmilyCJ in reply to Foggyme

Thanks I know not to supplement selenium without doing a test as it can become toxic in high levels. It's something I haven't touched as can't afford the testing.

FoggymeAdministrator in reply to EmilyCJ

Good to know EmilyCJ 😉😀. And I shouldn't worry about gene (MTHFR) testing...

This is what the genetic testing company 23andMe have to say on the topic...

Our Take on The MTHFR Gene," is a 23andMe blog posting (January 5, 2017), a meta-analysis finding that the past two decades of scientific evidence as it relates to specific MTHFR-influenced health conditions to be inconclusive or conflicting, with two exceptions, 1. women with two copies of C677T variant, 2. a very rare variant that may cause homocystinuria. Their takeaway, "Based on the existing data, scientists at 23andMe have concluded that people should not interpret their genotypes at the common MTHFR variants as having an effect on their health."

23andMe have now removed MTHFR from their testing regimes.

Worth noting that both methylfolate and methylcobalamin made me feel very ill indeed (though some do benefit - although sounds like this may not be you).

Don't want to replicate previous discussions in this thread so...your idea of trying low dose folic acid (400mcg) daily is a good one (5mg is a very high dose and usually only prescribed to those with a severe folate deficiency - and it can cause side effects for some, when taken in high doses). If you're still low on folate when tested, taking 400mcg daily as a maintenance dose will raise your folate levels.

Here's more information about folic acid supplements (including possible side effects):

Good luck...and post again if you need more advice 👍

EmilyCJ in reply to Foggyme

Thank you - I will try the 400 dosage. Just panicking a bit about tolerating anything and know I do need some as levels no right on their own. Though perhaps the 5mg was just far too much. I know the Facebook groups say this is absolutely necessary when injecting frequently though and that confused me.

I started reading about genetics and it absolutely blew my mind and scared me to death!

FoggymeAdministrator in reply to EmilyCJ

Well...the Facebook group is not correct....taking 5mg folic acid is not necessary when injecting B12...and there is evidence emerging that taking high doses of folic acid long-term may be harmful (neuro-toxic etc.)!

The qualification here is that some on certain medications may need high doses of folic acid (because the medications impede absorption)...but this is prescribed by a GP and managed via regular testing of folate to ensure that levels do not rise too high.

When I was first diagnosed, I did join the Facebook group but left quite quickly.

About genetics - it's ferociously complicated. As unique human individuals, we all have many gene variations...and very few of them translate into actual health conditions. It's also the case that gene mapping shows variations but cannot factor in environmental factors / unique medical histories etc....and these are implicated in any expression of health issues. So...just because a gene variation is detected, it does not mean that bad health or a particular medical condition will ensure.

There are some (but few) gene variations that are such is a particular gene that is predicative for Alzheimer’s - but personally, I wouldn't want to know about that! Another is the gene for Huntington's Chorea (usually only offered where there's a family history). But...

When gene testing is undertaken via the NHS it's done under controlled conditions and those concerned are offered counselling prior to testing.

And because it's so complicated, gene mapping can only be interpreted properly by highly qualified medical professionals.

So...the bottom line is...I can understand you being scared to death...but...there is a lot on nonsense on the internet....particularly in relation to MTHFR gene variations...often put there by those who have products to sell.

Interestingly, I did spend quite a lot of time looking at one such site, which contained a comments and questions section for people to get advice. Most of the many comments and questions did not receive a reply...and those rare ones that did (who expressed that they were feeling very ill) were most often told that they were taking too much methylfolate!

So go figure...

Best advice I can give is to not worry or think any more about genetics...😉😀.

Hope things begin pick up others have said, it can be a long road to better health...with plenty of hiccups along the way 🤨. Keep at it, keep strong...and try to stop worrying (ha - if only it was that easy).

fbirder in reply to EmilyCJ

Please. Don't read the Facebook group. It is full of nonsense. Many of them seem to enjoy finding the scariest stories on the interwebs.

Please don't worry about genetics. There is a lot of nonsense written about that on the interwebs. Especially about MTHFR. The company 23AndMe make a lot of money by testing people's genes. It is not to their advantage to put people off getting tested. Here is what they say about MTHFR.

Our Take on The MTHFR Gene," is a 23andMe blog posting (January 5, 2017), a meta-analysis finding that the past two decades of scientific evidence as it relates to specific MTHFR-influenced health conditions to be inconclusive or conflicting, with two exceptions, 1. women with two copies of C677T variant, 2. a very rare variant that may cause homocystinuria. Their takeaway, "Based on the existing data, scientists at 23andMe have concluded that people should not interpret their genotypes at the common MTHFR variants as having an effect on their health."

Ooops. Just seen SleepyBunny has posted the same quote.

EmilyCJ in reply to fbirder

Yes in particular the advice to take 5mg folic daily or injections won't work at all when doing them frequently was most scary to read being so new to this. I couldn't find any evidence that this was necessary other than them saying based on "their years of experience". Also saying to take 5mg methylfolate if folic not tolerated seemed insane as I lost my head on much lower than that!

Polaris in reply to Foggyme

Thank you Foggyme. Dr Izabella Wentz, is a qualified pharmist with Hashimoto's who has devoted very many pages of her well researched book to vitamin B12, folic acid/folate, selenium and MTHFR gene.

"Hashimoto's Thyroiditis - Lifestyle Interventions for finding the Root Cause".

As 40% of those with PA also have thyroid disease and vice versa, we are all different and, what works for some does not always work for others 🙂

fbirder in reply to Polaris

Methylfolate best as, if you have MTHFR gene, folic acid is not well absorbed.

Everybody has the MTHFR gene. Almost everybody (over 99%) have at least one mutation in that gene with no adverse effects. No mutation affects the absorption of folic acid. About 9% of people have a mutation (homozygous for C677T) that can cause adverse effects in a few people. Those with that mutation could benefit from supplementing with methylfolate instead of folic acid.

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