Pernicious Anaemia Society
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I gave the Sublingual tablets a try

but at 1000 mg i found it seemed to affect my sleep as made me quite

restless tossing and turning most

of the night as if i had had too much

caffeine before going tp bed and in the day time felt a bit

spaced out as if not quite here.

And felt anxious too which is not really

like me so i may try something different .I did get a slight headache the evening of my first hydro B12 injection and a bit restless but maybe

its because my last injection was 6

days ago so and due to the gap ?

Anyone else had this effect from Methyl tablets?

33 Replies

I haven't experienced problems you mention but there have been quite a number of posts from people who have. It does seem to kick off anxiety problems in people. You may find that you get on better with hydroxo sublinguals - you may have to hunt for them though.

I get most of my supplies from a company called detox-people and their range does include hydroxo sublinguals


Hi Gambit62

Thanks for the heads up

on the hydro sublingual tablets what you stated does make sense as i was on the hydro injections with very little side affects.

So will hunt those down.

Good luck.


Hi Advice1 have you tried taking the tablets in the morning? Just a thought...


Hi clivealive thats something i haven't tried

i may give it a try.I think

i read it on the forum that

another member took their Methyl Tablets

in the evening.So copied

their stance!

Thank you for your

kind advise.

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a ot of people - myself included - find that methyl helps with sleeping but responses to different types of B12 is very personal so what works for one person can have the totally opposite effect for another


i take first thing in the morning...NEVER AT NIGHT OR DINNER TIME or it does that for me too and i was also told to take a B COMPLEX WITH IT SINCE B VIT WORK BEST TOGETHER AND I WAS ON 5000 FOR 2 MTHS THEN 1000


Hi jacrjacr

Thanks for your kind advice and sharing .

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When I started taking methylcobalamin lozenges I had a revival of symptoms - burning feet, balanceproblems, dizziness were just some of them - plus hypokalemia symptoms (due to processes restarting, using potassium). I don't think it will allways work smoothly when you start correcting a deficiency - your body has had to work with less than the optimal supplies, and now it is sqeaking and creaking, trying to get back to normal business 😉


Hi. My circumstances are different, and I am fairly new to the site, but gathering useful help and information.

Quick summary in case you have not seen my posts! Doc diagnosed me 1 month ago with severe B12 deficiency, but purely from symptoms, and prescribed me B complex tablets with 10 mcg B12. Of course, as I now know, they would have had zero effect, which was the case! I managed to track down some Neurorubine-Forte tablets locally, which had 1000 mcg cyanocobalamin. I have been taking those twice a day for 1 week, and I was feeling a lot better, until today! Fell off the cliff today! The original symptoms have suddenly come back worse than ever! Yesterday, I was nearly bouncing, but today? Wham! Suddenly back to extreme fatigue and tiredness, feeling really nervous and trembling, right hand has gone numb again, dizzy, balance problems, chest and back pains, short of breath, and a new one with the left hand going a bit numb with all fingers twitching uncontrollably! Not good!

Unfortunately, I live and work in a very backward 3rd world country, where B12 injections seem to be unavailable, and sublingual B12 are not available anywhere!

I have ordered some Jarrow 1000 mcg on line, but they will take up to 6 weeks to arrive! If I live that long!

I feel as if my body has suddenly shut down! I just checked my temperature, because I felt as if I had a fever, but it is 35! Eek! Way too low! Possibly hypothyroidism?

BirgitteG, may I ask how long your relapse lasted?



A day or two for each of them!

If you're experiencing fatigue, it could be a sign of low potassium. Take a break with the b12, eat something rich in potassium whatever you can get, cut down on salt. Start again with only 1000 mcg a day, see how it goes! Do you get folate (not folic acid!) as well? And a full vitamin B (all 8)? That's important! Good luck, hope you'll be better soon 😊


Thanks for the advice , and support.

A day or 2 I can manage to put up with! Phew! It hit me hard to go downhill so rapidly and suddenly! Yesterday I was on top of the world and felt great, and then WHAM!

I eat a banana a day to top up the potassium.

I do not take folate, yet. I am still getting differing opinions on that? Some say to take folic acid and others say to take methyl folate? I will see what I can get from the local pharmacy tomorrow!

Thanks for your help.


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A banana a day is not enough if you experience fatigue and muscle cramps - can you get a supplement as well? Eat before you take them! I took 2 mg a day, a lot of tablets, hard to your stomach, but too little is dangerous, really!

Folic acid is the artificial kind of folate, folate should definitely be the best! And remember the vit B complex!

When you're okay with the potassium, and have got hold of folate and B complex with all 8, you can take up to 5 (some say 9!) 1000 mcg lozenges a day.

Best wishes 😊

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Folic acid is the artificial kind of folate, folate should definitely be the best!

For the vast majority of the population folic acid is just as good as methylfolate. Indeed, better as it has a higher bioavailability.

Are you sure you meant 2 mg of potassium? The recommended daily amount is 3,500 mg a day.

Most people only need extra potassium when they start B12 treatment and formation of blood cells goes into overdrive.

Too much potassium can cause fatigue, muscle pain and weakness. Way too much can cause death.

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Too little potassium are more dangerous than too much!

But thank you for correcting me ❤ - it certainly was 2 g (2000 mg) I meant!

(Down with a flu right now, but that's no excuse!)


Hi BrigitteG...Just to clarify for the sake on anybody reading...too much potassium IS as dangerous as too much...and can be fatal!

Potassium supplementation via tablets should only be done under GP supervision! 😀

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Just a quick update.

I feel a lot better today! I am buoyed by the fact that the "crash" only lasts a day or so!

Could not get any type of folate! Not available anywhere in this country. I have got some folic acid, so that will have to do!

I do not think I have a Potassium deficiency? I have no symptoms at all of Potassium deficiency. I do eat a lot of chicken, and a single banana has 350 grams of Potassium. If I start to get muscle cramps and nausea/vomiting, which are the main symptoms of Potassium deficiency, then I will look to taking Potassium supplements. Too much Potassium is just as dangerous as too little!

I did not get any B Complex, because the tablets I am taking are very high in B1 and B6, and I do not want to overdose on B1 and B6. That will change when I get the methylcobalamin lozenges though! I will start taking B supplements when I get the lozenges.

I have now ordered some Jarrow B12 sublingual 1,000 mcg methyl, from another supplier, and having them shipped via courier. Should be here in about 7 days, rather than the 6 weeks from the other supplier!

Thanks again for your support and advice.


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Hope you saw the fbirder's note on the amount of potassium above!

And allegedly folic acid should be OK. ...


I did see that amount! Time to put the record straight! It is actually wrong! The recommended daily intake of Potassium for an adult is actually 4,700 mg a day, which is usually obtained from a balanced diet. However, a normal person has no way of knowing their daily Potassium intake or levels! The important thing is to look out for the obvious signs of Potassium deficiency, which is listed as, •Weakness, tiredness, or cramping in arm or leg muscles, sometimes severe enough to cause inability to move arms or legs due to weakness (much like a paralysis)

•Tingling or numbness.

•Nausea or vomiting.

•Abdominal cramping, bloating.


•Palpitations (feeling your heart beat irregularly). Compare that with the symptoms of B12 deficiency? The only common factor is the tingling or numbness! We have to be very careful with self diagnosis!

And fbirder did also say, "Too much potassium can cause fatigue, muscle pain and weakness. Way too much can cause death". I notice that you obviously did see that comment!

My doctor diagnosed me with B12 deficiency, based on my symptoms, and we have to be careful to recognise the differences between B12 deficiency, and Potassium deficiency! Tiredness and fatigue are completely different! Nausea and dizziness are completely different! B12 deficiency causes Diarrhoea, not constipation!

I am a computer analyst and aircraft engineer, and I have to make sure that facts are facts!

So I am putting the record straight, so that people do not over analyze!

I have seen that a lot of people on this forum are pouring tablets into their bodies, which are probably doing more harm than good!

I will throw this open to discussion, but from what I know about my Mother, who has B12 deficiency. She gets 3 monthly injections, and that is it! The doc has not prescribed folate, nor potassium, nor B supplements!

From my research, PA only causes a B12 deficiency, and the associated anemia, and the treatment is B12 replacement therapy!

That is it, plain and simple! Replace the 1 missing vitamin?

The one thing that I would advocate though, is to take folic acid, or a folate, to promote the formation of the abnormal red blood cells that B12 deficiency/treatment causes!

People! Be very careful about stuffing yourself full of tablets!

You are probably doing more harm than good!

I also noted your comment, When you're okay with the potassium, and have got hold of folate and B complex with all 8, you can take up to 5 (some say 9!) 1000 mcg lozenges a day. Eh? Ok! You cannot overdose on B12, but 5,000 - 9,000 mcg of B12? C'mon! That is just plain stupid!

I am sorry if I offend your comments and posts, but I do not want other people to get the wrong idea, which I have to say that I think you do?

In conclusion. 1000 mcg B12 daily is the recommended dosage for severe B12 deficiency, short term, and then reduced when the balance is obtained.

B12 supplement, and possibly a folate or folic acid supplement is all that is really needed!

My good friend, who just happens to be a SNR, has told me to ignore your post entirely! Other people seem to be following this, and I say to them, be careful!



Hi Patez. just to,let you know...too much or too little magnesium can also cause muscle can too much or too little folate!

Supplements are a minefield and so difficult to get right!

Good luck 😀

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Hi Foggyme.

See my reply above!

I totally agree with you!

It is a minefield, if you happen to listen to ill advice!

If you take the time to do the research though?

It is actually fairly simple!

Treat the B12 deficiency!

Do not "introduce" Potassium deficiency, or Magnesium deficiency, or too much Sodium, or whatever!

Stick to the basics!

B12 supplements, and possibly folic acid (to promote the red blood cell formation), is all that is really needed to treat B12 deficiency!

Keep to the "KISS", "keep it simple, stupid" principle!

This is a PA support forum! Please do not "hijack" it with ill informed comments and false advice!

Enough said!



Hi BirgitteG

My symptoms are only a few but dont include fatigue i am quite the opposite and my


the serum potassium is ok and in the range.I only take 600ug Folic acid as locally haven't found Folate.But thanks for the advice

also taking B complex.I will follow your helpful advice.

good luck

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Hi BirgitteG

thats some interesting

points you've made.

Thanks for you input


I think patez is writing to me, obviously angry with me for my warning about the possible hypokalemia.

That's what happens.

Potassium can be dangerous if you take over 7 g a day. I never recommended something like that - but - whatever - just wanted to help.

.................... 😕

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Hi BirgitteG. Not so sure about that! See further replies...😀😀



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Indeed! 🤔🤔😱😱


Hi Foggyme.

It is a case of getting the right diagnosis and the exact symptoms right!

With all due respect! This is the PA forum.

B12 deficiency!

B12 has nothing to do with Magnesium deficiency.

Do your research!

I am tired, but I will take the time out to explain it all, which is explained in detail anyway on the home page!

PA, or whatever the cause of B12 deficiency, prevents the formation of Intrinsic Factor in the stomach lining, which then prevents the absorption of B12! That then creates abnormal red blood cell creation, leading to anaemia! It is very simple!

B12 deficiency and the consequential anaemia!

Nothing to do with Potassium or Magnesium!

Yes, it can, in very rare cases, end up with a Potassium deficiency, but definitely not a magnesium deficiency!

It is so simple to understand!

B12 produces Intrinsic Factor in the stomach lining! Without B12 though, Intrinsic Factor is not produced, so B12 is not absorbed! Result? Anaemia! B12 is responsible for the creation of healthy red blood cells! Without B12, red blood cells become an abnormal shape and cannot carry the oxygen properly! I am trying to put this into lay mans terms!

In reply to your post?

Yes, you are misinformed about PA!

Why you are "hijacking" the PA forum with Magnesium deficiency, I have no idea!

Muscle cramps can be one of many things! Potassium deficiency is one that I know of. I have never investigated Magnesium deficiency, so I will not dispute you on that.

PA does not produce Magnesium deficiency though!

I have read your posts though!

Yes! Too much Potassium is dangerous! So is B1 and B6! I cannot comment on Magnesium, because it is the 1st time that I have heard it mentioned!

Again! I put things into perspective though!

Look at the symptoms!

I have never mentioned cramps!

I do not doubt you, but cramps have nothing to do with PA or B12 deficiency!

Can I remind you and everyone else! The symptoms of B12 deficiency are,

•a sore and red tongue (glossitis)

•mouth ulcers

•pins and needles (paraesthesia)

•changes in the way that you walk and move around

•disturbed vision



•changes in the way you think, feel and behave

•a decline in your mental abilities, such as memory, understanding and judgement (dementia).

No mention of cramps!

So many people are complaining of cramps!

I will make this absolutely clear!

B12 deficiency does not cause cramps!

OMG! How can I hammer this into people on here!

It is very simple!



Patez. In an earlier post you talked of low potassium producing muscle cramps - and siad if you got muscle cramps you would consider taking potassium supplements!

Potassium supplements can be dangerous. And I was simply advising you that muscle cramps can have other causes (folate or magnesium imbalances).

For the avoidance of doubt - I was making you aware that there are other cause of muscles cramps so that you did not mistakenly overdose on potassium supplements.

I do not think that my reply was inappropriate but as you obviously did, I'll ensure that I no longer trouble you with any further replies in this forum.


Could you please refrain from telling others what this forum is or not is or what others should or should not write or have knowledge of ? That's more of an admin's job ...there was no hijacking going on.

1. PA is somehwat linked to low magnesium, because many of us have achlorhydria which can also cause problems with the absorption of magnesium and iron (among other nutrients) It is not só far fetched to mention it.

2. Foggyme was just giving a tip for cramps, it's up to you to do something with it or not. No harm in the tip. But you are right, you did not mention cramps (but other symptoms), but it was just a suggestion made, no need to for all the !!! in the posts and the personal 'attack'.

3. There are many more symptoms of a B12 def than the ones you mention. Muscle cramps/twitching/pain are mentioned as symptoms by some patients.

4. Too much potassium is dangerous, too much B6 can give problems, too much B1? Not so much...both folic acid and folate are fine to try out.

Other than that, yes stick to the basics especially in the beginning of treatment. Agreed on that.

As this is someone else's thread, I would suggest starting your own topic for your story, symptoms and treatment to keep the forum a bit more clear. Thanks.


Hi PAS Admin. Can I just clarify...Patez talked of muscle cramps, low potassium and taking potassium supplements in his third reply on this thread 😀😀.

Think the replies got out-of-sync, but that was the one that I was replying to.

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Just to make it clear PAS-Admin'sresponse was to Patez - layout on screen not clear because too many layers of response at the moment.

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I've experienced restlessness at night if I inject either methyl-B12 or hydroxo-B12 after about 7.30pm. I was actually warned by a doctor who gave me a private prescription that quite a few of her patients had reported this problem.


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