I have been on this forum for a month now and have been supplementing b12 for the same amount of time. I tested very low for b12 (159) as I have been vegan for 7 years. My symptoms were poor digestion, lost weight, low libido, anemia, and leg weakness.
I started a regimine of bi daily b12 shots as well as oral supplementation with sublingual and tablets. The initial response was a set of very strong neurological symptoms like twitching, dehydration, and anxiety for a week or so. Following that, I had great results with my symptoms. I had a stronger libido, better digestion, I gained some weight and felt strength in my legs for the first time in many years.
Now I'm at the month mark and my symptoms are returning with a vengeance even with 2-3 b12 injections per week and daily supplements. Bad weakness in the legs, foggy head, lethargy, very low libido. So I started off low, went up very high after starting supplementing, and now I'm lower than ever even without changing supplementation. I had my blood tested and my serum b12 is over 2000. There is plenty in my blood but I'm still failing here. It's like I've become resistance to the b12 now. Anybody have a similar experience?
Thank you
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lownskater52
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Hello. Have you been having every other day Injections as per bnf guidelines until no more improvements with that regime of IM hydroxocobalamin you shouldn't need supplements as well. It is a roller coaster though. Initially I got worse with every other day Injections. A sign of nerves waking up ect. Had a break and got ill again. Then restarted every other day and the best improvements were made. You may have been doing a lot more when you felt okay and it's caught up with you? Are you having your iron folate and vit D checked . ? Jjust ideas. I hope you get back on track soon.
I've slowed down a little bit to try to ween off but apparently I'm not ready for that. I went heavier on the b12 today and feel better already. I have been working hard and being more active which my be draining me as well. I've had both iron and vit d checked and they are both perfect.
It is not uncommon for some symptoms to appear to get worse before they get better as the B12 you are having starts repairing the damage done to your nervous system and your brain starts getting multiple messages from part of the body it had "forgotten about" or lost contact with.
I sometimes liken it to a badly tuned radio on which you have turned the volume up high trying to catch the programme you want when all of a sudden the signal comes in loud and clear and the blast nearly deafens you.
A lot will depend on the severity and longevity of your B12 deficiency as to how long before there is no further improvement or recovery.
Some symptoms will "disappear" quite quickly whereas others may take months or even years.
There is no set timescale as we are all different.
Fortunately you cannot overdose on Vitamin B12 as any excess is excreted via your urine.
The "every other day" regime should only continue until there is no further improvement in your neurological symptoms. This does not mean until all symptoms have "disappeared" as this may take several months or even years depending on the severity and longevity of the deficiency.
As Nackapan says it may well be that you need to have your iron and Folate levels checked as initially, replacing B12 will lead to a huge increase in the production of blood cells and platelets (which occurs in the bone marrow) and can lead to rapid depletion of folate and iron stores; this can then limit the expected recovery of Haemoglobin.
Both iron and folate may be needed so please have these levels checked by your doctor.
Also pathways may be broken especially if low on B6. The new active B12 test is needed. I believe you can overdose as everything needs to be balanced if not you will suffer other nutrient deficiencies
Sharcott. For. Clarification...although the active B12 test is thought to be more reliable that the serum B12 blood test....it still only shows how much B12 is in the blood, not how much is in the cells, where it,s needed.
If you are referring to 'overdose' in the sense of overdosing on vitamin B12...it is not possible to overdose on vitamin B12. Any excess is excreted in the urine, nobody has ever determined a safe upper limit (there is no upper limit!)...and it’s used in multiple 5mg doses IV to treat cyanide poisoning.
It shows 'active' B12 that is in the blood and hence available to cells. Like the serum B12 it does not show how much is actually taken up by the cells.
So both the active B12 and the serum B12 tests only show how much B12 is in the blood. The difference being that the serum B12 test shows the total amount of B12 in the blood, and the active B12 test 'splits' this down to active and inactive B12 (roughly 20% and 80% respectively).
Neither test can tell you how much is actually getting into the cells and being processed properly for ongoing distribution to all areas of the body.
A test to show deficiency at a cell level is called methylmalonic acid (MMA). This is raised if cells are B12 deficient.
If you read the fourth and fifth PAS pinned posts to the right of this page (at the bottom if using a phone)...lots more useful information there.
hi I am unable to take oral iron etc I am going to buy B12 inj online as I have tingling and burning of my legs and my balance is poor My B12 is 297 of course dr days that is fine. LOL. If I need folate and iron due to B12 inj them how so I get it into my body as I am intolerant yo oral supplements ? THanks.
Hey lownskater52 ! After one month of injections I was worse too (and even experiencing additional symptoms) which took me by surprise as was expecting to improve, not worsen. Now at the 2.5 month mark of supplementation (injections only, no sublingual or anything else) and just starting to experience a general feeling of stabilised improvement. Even after reading so many posts on here (to keep me inspired) about the length of time it takes to heal and the ups and downs along the way, it has still taken me by surprise I'm still experiencing symptoms - fuzzy vision, ringing ears, shortness of breath, lump in the throat, dizziness (still doing the knicker dance trying to get my boxers on in the morning - lol) - but way more manageable than a month ago. Clearly there is still a ways to go for me and know that 2.5 months is not really that long when reading other posts on here. Very very grateful that at least it's manageable now. Also agree with Nackapan , for those times when experiencing an up period, I was tending to get excited and doing a lot more, which would catchup with me a few days later and start to feel worse again. Take care brother
Wow. Lots of similarities. My ears are ringing like crazy right now, I've had dizziness and trouble concentrating, and my legs have been weak. This has apparently amplified since slowing my b12 intake to try to slowly wean off. My serum b12 is >2000 so I figured I can slow down but apparently not. How often are you getting injections? I'm at 2 to maybe 3 times a week. I was also feeling better early and got much more active after that which slowed my progress.
It's only in the last 2 weeks that I've been confident enough to reduce to 1 injection per week as have had a few weeks of sustained improvement. Up until that I was 2 injections per week. Learnt early on not to over-do physical activity when going through a good patch, as it always came back to bite, soon learnt if I was going through a few good days to just rejoice and enjoy some well earned quality rest and conserve energy for the next down patch. I'm like being fit, so had to swallow the ego and give up all intense physical exercise (i.e. yoga, running, hiking, stair climbing) and just went for casual walks and gentle stretching. It's only in the last 2 weeks I've been very gingerly resuming physical exercise bit by bit, so far so good, slowly does it though. My symptoms are similar to yours. Maybe you're not quite ready to wean off your B12 intake just yet, took me over 2 months before even looking like maybe easing off. You're plant based like me, and have made alterations to my diet to include more B12 sources i.e. B12 fortified nut milk, vegan sausages and mince fortified with B12.
That is some great advice man thank you. I'm going to follow it for sure and keep up the b12 for now. I'm glad to hear you've increased your dietary b12 intake while staying vegan. No reason to go back to animal products.
I agree. I was actually killing myself at the gym when I was diagnosed. Doc said due to my megoblastic state that I didn't have enough oxygen to support everyday function much less forcing it on my body walking treadmills. He also said that it causes the body to increase the adrenal response and causes a fight or flight response and the system essentially shuts down more and you run the risk of heart attack and stroke. This in turn increases the cortisol in the body defeating the exercise result altogether. I was actually prohibited from any activity other than walking for about 6 months.
This is a real concern what I am hearing, it's not all about B12, yes being vegan is a problem if you are not eating fortified foods or taking vitamins, this needs to be daily, you need B6 and folate daily also, Taking too much B12 can cause problems, so yes I believe you can take to much, but I will get shot down. What is your thyroid results? I was taking methylcobalamin daily at one point I had to until I found out my problems were all about dairy, not taken B12 now for 2 years, find the cause.
I'm still trying to find the cause. I'm also finding test only thing that seems to help me is b12 injections. I'm sticking at 1 every 2 weeks at present. I think I may pay and go back to a neurologist. Also looking into behaviour Optometrist. Both costly as the neurologist has discharged me on amitriptyline up to 150mg. As I'm not taking that nothing is masked at present. Out of interest how did too much b13 cause problems for you. The neurologist saud the same. I thought you cannot 'overdose' on it. Or perhaps you just didn't need it?
Yes I agree that B6 and folate can be Toxic but if you are having a lot of B12 it can deplete other nutrients. I know B12 is not Toxic. Am I wrong saying it can deplete other nutrients and vitamins in high doses
Hydroxocobalamin is a man-made injectable form of vitamin B12 used to treat low B12 ... pernicious anemia) This medication may cause low potassium levels in the blood ( hypokalemia). This is also what I found out at the convention I went to.
Yes...it may...but only if macrocytic anaemia is present when treatment first begins...not everyone has this and if it is present, this rectifies very quickly once B12 injections are commenced...and so is not an ongoing issue when having B12 injections. Usually managed via high potassium diet rather that potassium supplements (these can be dangerous and cause cardiac arrest - only prescribed by a doctor in cases of severe potassium deficiency).
So, having low potassium levels has nothing to do with 'having a lot of B12', or, with B12 being responsible for depleting other vitamins and minerals or indeed with having high B12 levels (what I think you original points were were).
Sharcott. High doses of vitamin B12 are not an issue (for reason I don't have time to discuss right now). Regular forum members will be well acquainted with those reasons.
Sorry, but your son is wrong (as you appear to imply, below).
Lownskater52. Some good responses here. 'Spect you already know but just wanted to clarify that B12 is not toxic, you cannot overdose on it, and recover from B12 deficiency can take some, with many backwards and forwards steps along the way (as others here have said).
There is no such thing as B12 resistance. If you feel that you've stopped improving or are going backwards, this may because of the vicarious nature of repair processes, deficiencies of other vitamins (iron, folate and vitamin D are prime suspects) or another underlying cause (hypothyroidism, diabetes etc.).
Please also note that over supplementing with folic acid and vitamin B6 can cause neurotoxicity...so sweats best to get levels checked rather than supplement on a 'just-in-case' basis.
Think I did suggest previously that you stopped methylcobalamin oral supplements (some react badly to those) and just rely on the hydroxocobalmin injections?
Thanks foggyme. You've got s bignhesrt for helping so many people on here.
As for me, I've been sublingually supplementing daily with a methyl/adeno blend and getting two jabs a week of alternating cyano/methyl. It's been almost 6 weeks now. I am now experiencing tingling in my feet, tinnitus, and pronounced leg weakness. The tingling/pins and needles did not exist for me prior to starting this heavy b12 supplementation. All of my co-factors have come back fine (thyroid, iron, ferritin, potassium etc) with every test. My serum b12 is 2000+. I'm concerned to say the least. My hypothesis is that my body has become dependent on massive doses of b12. Not sure there is anything else I can do...
Lownskater52...You cannot become dependant on vitamin B12...however much you take. And any excess is simply excreted in the urine. It's not toxic or addictive.
Some people are affected by the fillers in oral / sublingual supplements and some react badly to methylcobalamin.
Might be worth dropping the methylcobalamin and adenosylcobalamin to see what happens (some can't tolerate adenosylcobalamin cobalamin either).
You don't mention folate - assume levels are okay?
When treatment for B12 deficiency beings, many people report an apparent worsening of symptoms (with new ones appearing) before things start to improve. This is thought to be due to the 'repair' effect - cells, tissues and nerves previous deprived of B12 start repair (wake-up, if you like) and the brain has to recalibrate to interpret the new signals. This may be what's happening to you (your B12 level’s were very low). And repair and recovery doesn’t happen quickly so it’s early days for you.
Worth pointing out that B12 deficient is not the only potential cause of neurotically symptoms - there are many others. Here in the UK referral to a neurologist is recommended for those who have neurotically symptoms so that other potential causes can be investigated and ruled out.
And please remember...there's no such thing as B12 resistance or B12 dependancy. Making those assumptions buy into the most mistaken and dangerous thinking...unfortunately shared by some very ill-informed doctors. 😉
Often, along with a B12 deficiency, there are problems with folate, ferritin and Vitamin D being low too. Also if it's Pernicious Anaemia, since this is an autoimmune condition, other autoimmune conditions could be present as well, such as vitiligo, psoriasis, thyroid problems especially Hashimoto's. Sometimes more than one.
So quite often, once all deficiencies (and low-end of "normal" range!) have been picked up, a good daily multivitamin and mineral supplement will help, but if there are other autoimmune conditions, obviously specialist help will be needed.
There is a difficult balance to be had here; too little or too much folate and ferritin will both cause problems, and both folate and ferritin can take a while to get replenished.
Often people here report getting worse before getting better - perhaps because the balance has not yet been found, or maybe because the body needs to become accustomed to the influx of B12 after being deficient, and subsequent repairs to nerves etc.
However, there is no evidence currently that "too much" B12 has any adverse effects, since any excess will be dispersed in your urine. In fact, B12 in very large doses are used as an anti-toxin in hospitals. There is also new evidence emerging that will demonstrate clearly why some people need more B12 than others to control their symptoms (not cured) - further research in this area pending. Years and years of anecdotal evidence for this can already be found in abundance on this forum !
Despite the lack of medical evidence, common anecdotal evidence from this forum will lead you to expect a few spots, especially initially. For a few unfortunate people, that might be more than just a few and these might take a while to clear up. I usually get a couple even now, years later, when I have recovered from a "blip" (return of symptoms for unknown reason) and these will go again once I'm back on track. I consider this a positive marker, and a very small price to pay. Likely to be a sight more devastating if you're a fair bit younger than me: I'm 61.
Being vegan should mean that you are able to absorb B12 orally, after getting levels stable again. There again, being vegan does not prevent you also having Pernicious Anaemia. I would try to ensure a good oral B12 supply daily without compromising beliefs by fortified milk, certain fortified cereals and/or tablet, sublingual or spray. May involve some maths at first.
Frequent injections will mean B12 serum levels above range (>2000ng/L), which is why my GP no longer sees any reason for blood tests to include B12 serum test. She is aware that I now self-inject after deteriorating on every frequency offered to me on the NHS.
I'm not sure you can possibly be b12 resistant. You can have issues methylating though It's a biological component to almost every cell in your body so only in the conversion processes can it go wrong thanks to the mthfr gene. Most people do not know if they have this gene. But never fear! It sounds to me like you're experiencing symptoms from low cofactors unmethylated/ wasted b12 due to lack of metabolizing factors. With every 1000mg dose of b12 you need that same dose in folic acid. Now, if you are taking b12 in cyanocobalamin form, you may not be able to mythelate on your own. I would be sure you are taking the methyl b12 so you can get the converted b12. *(If you are not methylating you will also need folinic acid, the more pure form of folic acid. ) OR, Better yet, spend the 10 dollars more; go with hydroxocobalamin or adenosycobalamin as they are more pure and stay in your system 3 times longer and is easily down stream convert to methyl so your body doesn't have to do the work. Plus these two take the cyanide traces that cyan. Leaves behind out of your system. In addition, you're are anemic so much of your soreness and fatigue can be from low iron. Iron daily plus vitamin c (they Need each other) and avoid calcium or dairy because it will keep you from absorbing the iron. Given you're vegan that shouldn't be an issue. In addition, be sure to take at least 3 times a week, potassium and magnesium in addition to a multi vitamin. Also gave your vitamin d looked at. Almost everyone is low sns nearly half are deficient. I take 50,000 I a week for 6 months then a multi vitamin only for 6 months and then repeat with iron again. It is not enough to just take b12 injections or pills. If you are deficient in b12, you will not feel better until you get to a normal range and a good range with your b12 and the use of cofactors. I was diagnosed with pa in 2017 by an internal meds doc. He fortunately was well versed in the process and cofactors. I was blessed he diagnosed me on first visit and lands and that he knew not to just give me injections alone. Within 1 year my levels were as follows: b12 start 98 b12 now maintained at 966 (950-1000 on average) vit.d was 17, now 49. I'm not anemic. But I was so low and so bad off at diagnosis, but within 4 months my brain fog dissipated. Six months after that, my fatigue and soreness dissipated. After a year and a month I wad completely back to normal. My challenge now is that my thyroid is slowing down so they suspect hashimoto's because 90 % of hypothyroid is related to an addition immune disorder. Good old polyendocrine disorders such as lupus, ms, diabetes t1, hashimoto's, etc. Good times!
But for the last 6 months, I have not had any injections at all. Im taking hydrox. B12 with folinic acid once a day losenge. Met. b12 with intrinsic factor with folic acid (one pill I truly recommend) once a day, sublingual. Three days a week I take iron, vit.c ,magnesium, potassium. I have maintained and even increased levels with orals. It can be done because the daily rec is 2.4mg, by taking orally the hydrox it stays in your system so much longer you just keep topping off. Plus it removes the cyanide in your system from cheap cyan. But, first you must get to a good level in injections and cofactors so that the orals benefit you. You would have to take about 10,000 mg a day for like a year to be able to absorb 10% of that dose and truly raise your levels without injection. if you are afflicted with pa. If you don't have pa, or don't know for sure, you should be tested because you should be able to absorb b12, unless you're taking acid reducers or have some gastritis going on. Just give some of the above a try as you have nothing to lose. It can't make you feel worse... this is just what had really helped me. First and foremost, speak with your doctor. I only think if you take b12 alone, in any form, that you will not benefit from it without its cofactors. When one chain link twists they must all. With each large dose; you deplete a cofactor and you raise another one that supports it.
'With every 1000mg dose of b12 you need that same dose in folic acid'
The usual dose of B12 per injection is 1mg...(not sure where 1000mg comes from, unless you mean this is an aggregated dose over time - that is a hugh dose and would never be injected as one dose)?
There is no correlation between the dosage of B12 and a requirement for folic acid. Injecting frequently with B12 does not automatically necessitate a need for additional folic acid supplements.
Folic acid is given in 5mg dose for three months - but only in the presence of a proven folate deficiency. Some can maintain folate levels once and original deficiency has been addressed, some may need maintenance doses of 400mcg daily, and some may need slightly higher levels of folic acid for a maintenance dose. It's always best to work out what the individual requirement is via regular folate testing until an appropriate level for an individual is achieved and maintained. Over supplementing with folic acid long term can cause neurotoxicity and potentially irreversible neurological damage.
Potasssium Supplements: please do not take these unless prescribed by an appropriately qualified medical professional. Potassium is finely balanced in the body and taking supplements, unless there is a proven deficiency, can cause cardiac arrest. If there are any concerns about potentially low potassium levels, it's best to increase potassium in the diet and ask a medic to check potassium levels.
Iron supplements: these should not be taken routinely or on a 'just-in-case' basis. Always get a doctor to test ferritin levels (and preferably a full iron panel) so that iron deficiency anaemia can be correctly identified and appropriate doses of iron prescribed (if required). Taking iron unless needed can cause a condition called iron overload, which is very dangerous and can create long-term health issues. It's also possible to have low ferritin levels and NOT need iron (I.e. in anaemia of chronic disease) - taking iron in these circumstances can cause iron overload (we have seen this before in the forum).
It's also worth noting that oral B12 supplements are not the recommended treatment for PA, in the U.K., and indeed, do not work for many people. Where neurological symptoms are present, treatment is by B12 injections only (as per BSCH, NICE, BMJ guidelines etc).
Hydroxocobalamin is the form of injectable B12 routinely prescribed in the U.K.
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