Pernicious Anaemia Society

Bad reaction to Methylcobalamin tablets - not sure whether to self inject Methylcobalamin now!

Hi everyone,

I was diagnosed with PA / low B12 a month ago, my blood levels were 148 (should be between 180 - 1000 apparently). I'd been feeling ill for about 3 weeks before I was diagnosed.

I had the five loading doses of Hydrox, I don't feel much better but it's early days. My problem is my doctor. He literally doesn't have a clue. He told me my blood levels aren't that low and some people have a b12 level of 2 (wtf??). I asked him for monthly injections but he refused, he said I'd need a blood test in 6 months and if still low then I could have more injections. So he basically wants me to go 6 months without injections.

This is a stupid idea to me, I did a lot of research and ordered sublingual methyl tablets online, and injectable methyl. The tablets came first, I took one yesterday and omg I have never experienced anything like it!! My heart was racing, my anxiety went though the roof, all on just a pill!!! I am now relucant to inject the methyl, it's a shame because I ordered it from Germany so can't really return it, I've wasted £35 :(

Does anyone here inject Hydrox?? Just looking for the best advice on when to do

16 Replies

This reaction is probably an indication that you really need the addition B12. Methyl is just a more active form and is directly usable. You were probably having a reaction to the metabolic byproducts. This is sometimes called detoxifying. You get symptoms from it.

Are you also supplementing with folic acid? B12 needs folate to do its job. I get a similar reaction to yours when I get too much folic acid. 5 mg is the max daily prescription but I can only tolerate 3.2 mg

I take methyl 5000 mcg 2x sublingual tablets before meetings to clear my head and to think. Or just to fill in between injections when I feel low.

I recently injected IM methyl that I got OTC on a business trip to Riyadh. I noted very little difference, but I'm self injecting cyano weekly so probably not as low on b12 as you may have been.

Keep a log book of your symptoms and try to assess a severity score for each of them. Your own scale is fine. Monitor how your symptoms react. Some are due to the deficiency and some very similar ones are a result of getting the b12. It is all a matter of timing.

Food and meds also play a part. There is usually a 3 to 48 hour delay because the gut is involved. When you have a symptom, look back in your log for a possible cause.

Remove the suspect item from your diet for two weeks to let it get completely out of your system before reintroducing it and monitoring for the symptoms.

The log book also serves as a good talking point and "evidence" for discussions with your doctor. Discuss your plans with your doctor and make a partnership but let him/ her know that you have taken control and need their help guidance and prescriptions.

I used this method in the U.K. And the USA to get more frequent injections and even to convince the surgery that I would start to self inject.

Wait a few days and try the methyl tablets again and see if the reaction is less each time. Then inject the methyl when you see no reaction to the tablets.


Hi, thank you for your reply :)

I am taking 400µg of Folic Acid (Methylfolate), so that's 0.4mg , 5mg seems an awful lot,

I've recently started taking a lot of new supplements to help with this (including L-Glutamine, folic acid, probiotics etc.)

I've read a lot online and reviews for the sublingual methyl tablets, the reviews have all been great, no body mentioned anxiety so that was what made me think that I am just not suited to it & would be better off with methyl, I am very scared to try the tablets again I almost had a breakdown at work! But if it's all part of detoxing I'd carry on I'm just worried that I'm very sensitive to it or allergic :( I felt much worse after the methyl tablets than I did after the hydroxy injections (but I didn't feel great after these either)


Have you looked at either a gluten or dairy (casein protein) issue?


Also anxiety is just another B12D symptom. Makes things confusing.

Stressing out also consumes B12 so start a log book and get a handle on which symptoms are connected. This way you can take control of your symptoms and start to relax.

I had all these same issues and worries before I got the dosages right.

You are your own experimental subject so the log helps you sort this all out. It also serves as your short term memory, which is also failing due to the B12D.

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Not everyone responds well to methyl cobalamin - to be honest reactions to different types of B12 vary a lot.

You can source hydroxo from germany (most of what's used here is manufactured there)

Methyl doesn't really do anything for me on the anxiety depression side - hydroxo (and adenosyl much better). I tend to use nasal sprays ... and I do use a mixture which includes methyl as it helps a little with some of the numbness in my left foot and also with sleeping but also inject hydroxo - particularly if I'm going to have a stressful day or going to be doing a lot physically.

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Hi, thank you for your reply, the nasel spray sounds like a good idea, I've been taking a sublingual spray but it's done nothing for me, where do you get the nasal sprays from?

I am definately going to order hydroxo online to inject. All I've read every where is how methyl is the most superior type of b12 but my reaction was terrible :( Do you take methylfolate? I've read everywhere you need to take this to absort b12 & I started taking this but now I think this could be contributing to my anxiety.


I don't take methylfolate - and for some people it really doesn't work.

In theory methyl is closer to the form used in cells so should work better but it can actually set of reactions in some people - the methylation process seems to be particularly sensitive to genetic variations.

I just use plan folic acid.

I get nasal sprays etc from detoxpeople.

You might find this interesting in relation to methylation


Hi, I am going to order the nasal spray on that website, can I check is it 500mcg Hydroxocobalamin spray that you use?

Thank you for all your help


I use both the Yuliv spray and also the nasal drops - which is partly to do with how easy they are to carry around (Yuliv can leak).


Ah ok do you use Hydroxy - 1000mcg or 5000mcg for the drops? Also how often do you spray / use them a day?


I use both hydroxo and methyl drops - for hydroxo I use the 1000mcg drops that I use.

I get through a lot of B12 - if I was just using hydroxo I'd probably be using 1000mcg 3-4 x a day. You really need to listen to your body on how much you actually leave.

I have various relatives who use the Yuliv - my aunt finds that 1x500mcg a day is fine for her - my brother uses even less than that. My mother seems to be the same as me - so obviously a very individual thing.


I brought the spray! I've been using it 2x per day & it has perked me up, by the evening I am exhausted though, I don't take it after 2PM and I am concerned that I'll be kept awake!

Can I check do you take it in the evening? & does it affect sleep? & also do you space it out e.g. once every 4 hours?

Thank you!


Cobalamin also helps to regulate the sleep cycle - there have been times when I've had problems in the night and used it to help me get back to sleep.

No guarantees as everyone is different but there shouldn't be a problem using it after 2pm



I'm sorry to hear that. I can take lots of the sublinguals with no adverse effects. There is a voluntarily run charity, that can be accessed through the Facebook support group, that can provide supplies FOC to sufferers without funds. Maybe they will swap your methylcobalamin for hydroxocobalamin?

It is a closed group and you can ask to join at

As with here, there is lots of information and help available.

I take folic acid tablets rather than anything more technical and expensive, eg methyl folate. They are just as effective for many people.

Good luck!



I have weekly injections of methyl and have always done fine with them except for once when I had a terrible anxiety reaction that came and went for about 24 hours.

I was reluctant to get another shot of methyl but in general it has helped me so much and I need it, so I went for two weeks before getting another shot. I did not have that same reaction. No anxiety! Since then I have never had that reaction again and am back to once a week injections. I also use a methyl spray a couple of days before I'm due another shot.

I was on Cyrano for a year, once a month shots before I switched to methyl and it did

absolutely nothing for me.

I can't tell you what to do, but just wanted you to know that the anxiety I had was just a one time thing!

Maybe it is as pvanderaa says, that it is metobolic by products.

Best of luck to you!


Do the tablets contain anything else in addition to the methylcobalamin?


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