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Can a high B12 cause a racing heart for long periods of time?

Southy12 profile image
29 Replies

Hi there,

Thank you to those who replied to my last post about high B12 and high folate after injections. My thyroid testing arrived to day so I will send that off tomorrow.

I’m still having rapid heart rates through out the day lasting hours and they keep me awake at night unless I take a very strong prescribed sleeping tablet. I get incredibly shakey and cold still and the ringing in my ears gets worse, very impatient etc. It feels like someone has given me 10 coffees most of the day and it’s been 8 days of it.....It’s horrendous!

Has anyone experienced this?

I saw a different GP today as mine is away. I asked to be checked for Type 1 Diabetes because of my symptoms and my last blood test said I had borderline blood sugar for diabetes and I eat a Paleo diet. This result was normal. ECG said my heart rate was a little raised but fine. He said the rapid heart rate I was experiencing at rest ( 55 to 110) was because my kidneys were having to get rid of the high B12 in my blood from self injecting. My bloods had said my B12 was over 2000 6 days ago after my last jab.

Could this be true that my self injecting has caused this? I only self injected early as I had neurological symptoms returning at 5 weeks. He was not interested in guidelines.

I don’t know whether to inject in case my racing heart gets worse. I never had this symptom before injections began.

Could I be sensitive to Hydroxocobalamin?

I have also been gluten free for 5 weeks which has Helped with lots of my intestinal problems and will try giving up dairy to see if this helps.

Sounds silly but this GP has scared me to inject!

Any thoughts would be helpful! I wish all well out there!

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Southy12
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29 Replies
Sleepybunny profile image
Sleepybunny

Hi,

I wondered if your potassium levels are being monitored? Some people experience a drop in potassium levels (Hypokalaemia) when B12 treatment starts.

bnf.nice.org.uk/drug/hydrox... See Side Effects section.

b12deficiency.info/b12-trea...

nhs.uk/conditions/Potassium...

I hope your GP is able to help you.

I am not medically trained.

Southy12 profile image
Southy12 in reply to Sleepybunny

Hi Sleepybunny,

I just went to look up my results and realised that the normal reading for potassium was the blood test I had showing I had PA. My GP seemed to test everything last week but not electrolytes etc. So I thought my levels were fine.... that’s my jelly brain as I call it. I eat a banana a day but have ulceritive Colitis too so I will def look at this! Thank you!

Gambit62 profile image
Gambit62Administrator

personally I think your GP is talking out of a part of his anatomy that is closer to his kidneys than his mouth but I'm not medically qualified.

Never come across the theory that high doses of B12 cause racing heart before - if it was the case then I'm sure it would be listed as a consequence of using hydroxocobalamin to treat cyanide poisoning but it isn't - that uses 5000x the amount you have in an injection, administered intravenously - and the big risk is raised blood pressure because of the amount of fluid that is being injected.

Drumstix profile image
Drumstix

Hi Southy12,

I'm not a medically trained person in any way but thought I would just share my own experience with you....

I have a very nasty arrhythmia involving high heart rate which amazingly has remained undiagnosed for over a year, just that I know of! I didn't start B12 treatment and then self injecting until November 2017, so for me personally this was definitely not the cause of my heart issues. Who knows though if the lack of B12 may have caused them in the first place???

I would be inclined to agree with the admin lady. Adverse heart reactions to B12 would be very well documented if there were serious ones.

Good luck and I wish you the very best!

Drumstix

Southy12 profile image
Southy12

Thank you everyone.

I’m tempted to start injecting, even though 2 gps have told me not to. I know it sounds silly....I think because my head is so wired I can’t think particularly rationally!

Even when my heart rate is fine, it feels like it’s racing..... but it’s my head that’s racing all the time, it’s hard to tell if it’s a sign to inject or that things are repairing and I just can’t cope with the over alertness and stimulation that I’m experiencing .....the ringing in my ears and the noise of everything is so loud that maybe it’s making my head feel like this. I just wish i5 would let me sleep.

I haven’t had a numbness or tingling so have been very lucky in that respect, all my symptoms are more neurological symptoms with my head and neck. My hands and feet have been frozen now for weeks which makes me very shakey, do these sound like neurological symptoms? I wondered if anyone has experienced this and that maybe it’s a sigh of thing working/not working.

I don’t know how I would have coped the last 2 months without this forum, the knowledge and experience of everyone is amazing so thank you.

I know I have only posted when I am so poorly .... I hope when I feel a bit better I can give back support to people too!

MoKayD profile image
MoKayD

Hi,

I had a similar problem. As soon as I started my B12 injections my blood pressure started to rise. My doctor wasn't worried about this. He said he was more worried about my lack of B12 than my blood pressure. About a year into my monthly injections I had a horrible reaction to a B12 shot. My face turned bright red, my heart was pounding in my chest, I got a severe headache. I had horrible insomnia for three nights. Things started to calm down after about a week. I told my doctor about the symptoms and he told me that B12 was harmless. The next month the same thing happened. I was really scared at that point because I need B12 but a week of these symptoms was awful. I did a lot of online research and found a tiny reference from a doctor who had a patient react like this and he said he had his patient take antihistamines which seemed to take care of the problem. Before my next injection date I took a Benedryl and sure enough I didn't get the reaction. I did have to take antihistimines for about a week because if I didn't the headache and the rest of the problems would start up again. I made an appointment with an allergist a couple of months ago and brought along a vial of B12 which he used to test me for an allergy. I wasn't allergic to the B12 but he said that I was having a reaction, just not an allergic reaction. He recommended that I continue with the antihistimins and talk to my doctor about taking a beta blocker the day of my shot. Apparently my body is pumping out cortisol like crazy after I get a shot. I haven't seen my doctor yet but I will talk to him about the beta blocker soon. For the meantime the Benedryl is working great.

Southy12 profile image
Southy12 in reply to MoKayD

Hi MoKayD,

Thank you for your reply. I just wondered how you were getting on?

I have been injecting every other day and my reaction to the jab has been just like you describe. The pounding heart feels just like you say .... that I’m pounding out adrenaline/cortisol....not very knowledgeable on this. My body feels like it’s vibrating inside. I started taking anti- histamines this morning which seems to be helping control the pounding head and vibrating.....so thank you.... your post was re-assuring to hear as this is all so scary .......

I hope you are doing well ........your experiences seem close to mine ..... I hope you don’t mind me asking....I wondered if you have had any tests for thyroid done or any other tips that may of been use...

Best Wishes Southy12

MoKayD profile image
MoKayD in reply to Southy12

I'm glad I could help. I'm doing really well now. I think I mentioned in my previous post that I had visited an allergist. He told me that he had done a year of research at Johns Hopkins Hospital in Baltimore during which they studied patient's allergic reactions to medications. He said that during that year he had seen one patient like me who, though they weren't "allergic" to their medication, still had a strong reaction. I guess I was lucky to pick this allergist with my problem. I am still getting my monthly B12 shots but now start taking a Claritin in the morning and a Benedryl in the evening the day before my shot and continue to do so for about a week afterward. Every month I'm feeling fine after my shot so about three days afterward I say to myself, I feel good, I don't think I need to keep taking the antihistamine so I stop for a day, and sure enough, within a few hours my head starts to hurt and my heart starts pounding. Back to the Claritin.

I'm now trying to control my coritisol levels in other ways. According to my research, you should drink more water (I'm really bad at drinking enough liquid during the day.) You should try to control the amount of salt in your diet (I love salty snacks.) Meditation is supposed to be good for controlling cortisol levels so I'm TRYING to meditate though I'm not very good at it. Getting enough sleep is supposed to be very important so I'm trying to go to bed at a decent hour every night. The benedryl helps with sleeping. The other thing they suggest is losing weight. Once again, I'm trying to do this too.

I hope you continue to feel better. Good luck.

Southy12 profile image
Southy12 in reply to MoKayD

Thank you for this MoKayD.

Have you had your cortisol tested? I was thinking of doing this. I’m glad your doing so well.

I’m really struggling to cope.... I have a constant tremor which feels from inside me. It’s been constant for 3 weeks and is making life awful. I cant sleep or function and nothing seems to help. I have been meditating lots but the tremor doesn’t stop. I’m not sure if my heart is causing it as it just pounds. I’m seeing a neurologist tomorrow. I haven’t seem to have found much on people having a constant tremor. Maybe it’s nerves repairing ...who knows. I wish you continued health!

MoKayD profile image
MoKayD in reply to Southy12

No, I haven't had my cortisol tested but my allergist seemed positive that this is the problem. He also suggested I talk to my doctor about taking a beta blocker pill the day of my B12 shot. He said this would shut down my body's production of cortisol. I haven't investigated this option yet since the antihistamines seem to be working well. You might want to talk to your doctor about this option. Have you thought about cutting back on your B12 shots. I feel like my problems started when I started self injecting a couple of times a week. I'm back to my prescribed once a month shot now and while I feel like I could use a B12 shot after three weeks I'm afraid to up my protocol. I can't say I ever felt a tremor in my body but I do feel my legs kind of ache and tremble when I haven't taken a magnesium supplement for a while.

Southy12 profile image
Southy12 in reply to MoKayD

Thank you for replying. Everything got worse when I started self injecting. Have you experienced any burning?I have had lots since I started self injecting too. I never had any before I started the B12d treatment......

I’m such a mess..... I don’t know what to do...... GP not very helpful.....

Longone profile image
Longone in reply to Southy12

Hi Southy, what you describe is what I am feeling exactly!! Mine started before the injections but are worse after I had the first one. All my test but low b12 came back normal. Did you ever find what was causing the irregular heartbeat and shaking with coldness in hands?

Longone

Ctadds1 profile image
Ctadds1 in reply to Longone

Did you ever receive any further info on this. I experience the same thing.

Marymary7 profile image
Marymary7

After lots of reading on this subject I think all the advice above is excellent and particularly Sleepybunny with the excellent Potassium links, that really seems to explain a lot with the heart problems . Also I read that bananas are not so massive in potassium so you will need to check out some good foods rich in potassium to eat as well. Good luck.

Alesia profile image
Alesia in reply to Marymary7

I found Coconut water really helpful for the potassium, it has much more than most foods and really easy and refreshing to drink :)

Marymary7 profile image
Marymary7 in reply to Alesia

That's great, thanks for info. 😀 I will try that for my brother too.

Southy12 profile image
Southy12

Hi,

Thank you for both taking the time to reply. I’m not quite sure what is going on with me. There are so many variables to consider, that is very hard to make sense of everything. I have had the worst 2 weeks of my life, been to A&E twice, I’ve slept probably 10 hours in 12 days. I have had palpations and a constant vibrating feeling in side, like my whole nervous system is firing out of control for 7 days straight. ECG’s haven’t picked up anything apart from a slightly raised heart rate. I’ve had burning down my arms, legs, back and face for 4 days. Two GPS have implied that too much B12 could cause this..... one of them today......Thursday I started self injecting every other day as my feet felt like they were going numb. I have quite a few of the neurological symptoms, so have decided to ignore the GPS advice and go with all that I have read from experienced people. Something that I have found very hard to do as I am very sciencey! I have just had my third injection of every other day and now feeling so much better in that so many of the symptoms have been eased. The only thing that seems to calm my heart rate and the horrific vibrating from within, was a sublingual of Methylcobalamin, within an hour of taking ..... this was Sunday, 6 hours later it returned, I took it again and the palpitations and vibrating are just there slightly and it’s been nearly 22 hours! Which after 7 days of hell and psychotic thoughts is such a relief.

I am hoping that this is the start of a path to recovery but who knows..... I have slept for two days with the help of sleeping tablets. Something that was not working until the vibrations stopped.

My potassium levels are fine as was tested at the hospital and I have been adding the LoSalt and bathing in what was recommended for magnesium as well as being careful with my diet. I have stopped taking Folic Acid as my result was 22 a week ago, 2 months ago it was 3 after supplementing 5mg for 2 months.... 18 was the upper range.

I have read that too much Folic Acid in the blood can cause toxicity and symptoms. Not sure if anyone else has experienced this.??

I will start taking the daily recommended using methyol folate but not sure when I should start taking them as my level was so high........

I also stupidly took a supplement with high levels of B6 thinking I may be deficient as my folate was... esp given that my diet is so rich in folate.... I only took them for 6 days but enough to send my levels sky high if they were already good.... I know this can adversely effect people....... maybe I’m just clutching at straws to try and explain everything.

All I know is that I felt so disillusioned after seeing my GP today. Sorry for waffling on if you do read this ..... I just hope the vibrating does eventually go as it as ruined my life for 12 Days.

I wish good health to all!!!

Marymary7 profile image
Marymary7

Southy12 you poor thing, what a nightmare. Folic acid didn't seem to agree with my brother so now he has the Methyfolate so that may suit you too in a while. I did see a film on YouTube about people with certain genes having that problem. I have also read that your symptoms now sound like the nerves are awaking so that's good. It's too late for my brother he is paralysed down one side with a dead arm and very heavy dead leg...he gave in and accepted a wheelchair in his flat this week😔So you keep on trying, it's a harmless vitamin which you can pee out as you well know.

Good luck. 😀 X

Southy12 profile image
Southy12

Hi Marymary7,

Thank you for replying. It made me feel better!

I’m so sorry to hear about your brother. I hope you dont mind me asking........ did he get delayed treatment?

Did he react to folic acid?

I’ve started taking methyl folate today.... like you say, I know you can wee it out, but I thought the same of folic acid and my folate level ended up very high. I know I was taking 5 mg a day as my level was low but it makes me very nervous now taking anything. I’m only going to take it at the daily recommended to start and every couple of days. I’ve been gluten free for 6 weeks now so hoping maybe my absorption may have improved..... it’s all really guessing.... esp when you are new to this..... GPS don’t seem to have any real info or advice.......

Marymary7 profile image
Marymary7 in reply to Southy12

Sorry, I wasn't t notified that you wrote a reply . My brother was not treated. They blamed it all on M.S. I'm not sure if he has both problems. If you are interested in his experiences you click on my doggy pic on profile, and scroll down a few to the ones which have my brother in title. Very sad. I think he has subacute combined degeneration of spinal cord from being neglected by doctor...only gave him folic acid which you should never do without addressing the lack of b12/ Pernicious Anemia, Dr Chandy thinks so too and he has never examined or met my brother.

I bought all the great books recommended on here and joined the b12 orgs etc. I particularly like the Sally Pacholok book, Could it be b12.

Good luck.

sbadd profile image
sbadd

I know this is old post but i finished loading injections 10 weeks ago and in last fortnight my heart has been racing during the day, i did have a uti that was picked up and treated for ob antibiotics, since then heart continues to race and im now very bloated, my thyroid checked and fine on meds, all other side effects from injections have now passed as i had pretty much all horendous side effects, im wondering aswell if the high levels of b12 still in my system are causing this??? Ive also had ecg which normal, might try the antihistamine???

Deronda77 profile image
Deronda77

Not sure if anyone will see this but did the racing heart symptoms resolve? I'm having similar symptoms and have stopped self injecting at the moment.

Cherylclaire profile image
CherylclaireForum Support in reply to Deronda77

If you have a racing heart, Deronda77 , I really think you should see your GP.

Although "heart arrhythmia" is listed as a B12 deficiency symptom on some of the more comprehensive lists, it would be best to rule out anything else/other/new.

I had a thumpy heart that would wake me suddenly at night sometimes, and affect me sometimes during the evening after eating, or occasionally when lying down. I attributed this to my B12 deficiency (which was being treated) and ignored it as a fairly common symptom that would probably right itself over time.

A few years later, it changed: far more frequent, night and day, for longer periods and more severe, until it was happening several times a day and most nights too. Also caused some dizziness.

I went to the GP and had a 24 hour monitor fitted at the local hospital. It turned out to be "ventricular ectopics"- no known cause, uncomfortable but harmless, starts for no reason and can stop in the same mysterious way. Betablockers are usually prescribed, which slow down heartrate but I decided not to risk them, as I had been told by a doctor the previous year that I had "sinus bradycardia"- a slow heartbeat !

Luckily, it soon returned all on it's own to my normal - occasional discomfort but manageable.

Both my parents died from heart conditions - another good reason not to ignore any changes, I thought. Anxiety, also often mentioned in connection with B12 deficiency, might be reduced by eliminating any nagging fears as soon as possible.

Ctadds1 profile image
Ctadds1 in reply to Deronda77

Have you gained any info on this? This post is old but I am expediting the same thing.

Deronda77 profile image
Deronda77

Thank-you ❤ I am under the GP and have had 2 ecg's (the short ones) and have another one scheduled on Wednesday. At the moment they think anxiety (I have really severe health anxiety).

Initially when b12 and Iron deficiency was discovered I had palpitations. They improved after loading jabs and then in the two months after before SI they came back and then I ended up obsessed with checking my heart rate and as stuck home nothing to get me out of it. Had panic attack yesterday and heart rate was 90 at gp. Have spent all today fighting panic and went out to shops to stop all the pulse checking and just laying here now trying to write this I felt like my heart was racing and I eventually break and check and its only 80. I'm just sending myself crazy 🥺

Pollyanne96 profile image
Pollyanne96

Hello, I was prescribed cyanocobalamin for a b12 deficiency as well as iron tablets. The past two weeks I've had such bad chest pains and irregular heart beat I went to A and E, I looked up symptoms of b12 tablets and one of the rarer but still possible symptoms is irregular heart beat rapid heart beat and chest pains. Since stopping them 3 days ago my heart rate has returned to normal almost and I feel a lot better. So there definitely is a reason to believe b12 can cause this. I dont know why others are saying otherwise because if you look up side effects it shows up on several different websites.

Ctadds1 profile image
Ctadds1 in reply to Pollyanne96

How are you doing?? I am having heart/chest issues and inject weekly. I need the B12 but I’m not sure about what it may be doing to my heart

Izzi77 profile image
Izzi77

I had vitamin b12 shot yesterday. I am 44 yo and did it because I have been experiencing lack of energy. The first thing I noticed this morning driving to work was vision improvement. I could see everything so much clearer than the day before. Next thing it seems that my heart rate increased. I don't drink coffee because it gives me shakes and heart rate increase and today I feel like I had at least one coffee. I also have a little headache like I usually have after coffee. It my opinion vitamin b12 shots can increase heart rate. It's too bad because I really enjoy the improvement in vision and the energy I feel. I don't know if I will be able to continue because of the increased heart rate and headache.

Ctadds1 profile image
Ctadds1

How are you and did you ever figure out the reason behind your heart issues? Was it B12 related?

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