Has anyone here started taking B12 injections whilst on thyroid medication for hypothyroidism? And if you did, did the B12 affect the thyroid medication in any way?
I seem to be noticing a higher heart rate since starting B12 last weekend. But I have permanent atrial fibrillation anyway so my heart rate is always a bit unusual. However, I can usually spot trends and so far this is looking like a trend.
It could be theoretically possible for B12 to enable better conversion of FT4 to FT3 and lead to over medication and the need to reduce a dose.
I'm looking for anyone who might have experienced something like this.
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FancyPants54
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Yes, I have had an inverse relationship between my levothyroxine dose and PA treatment. When I was first diagnosed hypo I was put on 100mcg levo, but as my undiagnosed PA progressed, my thyroid function continued to worsen until I was on 200 mcg of levo. Once I was diagnosed with PA and began an aggressive B12 injection routine, I have had my levo dose reduced to 175 mcg and expect it to be reduced again as my TSH levels have continued to drop and now below normal. My endo feels that this and many other of my health conditions have been due to my body being more efficient in absorption. I am no longer on any medication for diabetes and my A1c has remained below 6 for several years now. Unfortunately, I have also put on 15 lbs thanks to this new, more efficient absorption. I was so sick for so long with repeated GI bleeds and iron deficiency that I got used to being able to eat as much steak, cake, and ice cream as I could manage and I would still lose weight. Sadly, not the case any longer.
Thanks for that. I'm sorry you have suffered so much! But you have described what I wondered if I might see. I'm ready to retest my thyroid shortly (another couple of weeks) so it will be interesting to see what the numbers are. I'm not bothered about TSH but I do need to know what my T3 is doing. Something is raising my heart rate during the day.
Is your endo dosing by TSH alone? If so, have you considered that lowering your dose may have contributed to your 15lb weight gain? If you don’t know what your FT4 and FT3 are doing and symptoms such as weight gain are presumed caused by better nutrient absorption and you continue to take less T4, other indiscernible (for the moment) hypo symptoms could be creeping back in. If absorption is improved then you d expect absorption of thyroid replacement also to be improved, so it’s very much worth checking FT4 and FT3. No, more than worth checking., it’s crucial
If on the other hand you feel really well and you know your frees are good, I.e., FT4 and FT3 are respectively at least 50% and 65% through the range then it’s less (however, still entirely possible) that being under dosed is the cause of your weight gain because many of us need our frees even higher, sometimes by quite a lot. Some are fine with theirs below that but by not too much
When my FT4 and FT3 were at 48 and 64% within range my weight just kept creeping up. Being simply “within” range is very often too low within range for that particular individual. If doctors paid as much attention to FT4 and FT3 as they do a low TSH, so many more of us would actually feel well and be of a healthy weight
Hey, me again. Yes, I have both & it can happen that as your b12 deficiency is treated & your levels increase you need less thyroid hormone. That’s why in the thyroid uk group they always emphasise optimal levels of b12, iron & vit d as they each play a role in thyroid hormone uptake. Oestrogen can interfere with the thyroid pathway too.
However, as the heart is a muscle, you can also get heart-related symptoms both as a result of the b12 deficiency & whilst you are recovering from the deficiency, so I have read. I’m not an expert in heart disease & others here may know more but, for eg palpitations are common in deficiency & whilst reversing out. So it may be a tricky one to navigate for you but hopefully, you will get some good advice on here.
This is what I have been thinking. The urge for optimal B12 and iron I have tried to abide by, hence stuffing thousands of B12 tablets, sublingual, drops and oil down my throat and then seeing high blood levels but still getting the neuropathy symptoms amongst others is why I have decided to try injections. And I've been thinking that if I were low on functional B12 and I started putting it into the tank I might notice better thyroid conversion and therefore more hormone.
My heart rate is a poor marker though as it can be fast for too little thyroid hormone or fast because there is too much. My temperature seems to be dropping. It's so hard to tell. I wish I could find a solution that worked more quickly. The mid to late summer and up to now I have had very swollen feet and ankles, especially towards evening. I've got away with it by wearing my Croc flip-flops. I still am. But it's going to soon exit flip-flop weather and then what will I do! I hope my extra large size boots still fit. For years I wore an 8. But in the last few years as my problems escalated, I had to buy size 9. Hideous. I may as well strap the boxes onto my feet.
I've not seen B12 deficiency symptoms of fluid retention/swollen feet. So it must still be down to thyroid.
Have you considered other factors that might be causing both peripheral neuropathy and palpitations? It could be completely unrelated to the new combination of thyroxine and B12.
I have been on thyroxine for 15 years and on B12, initially by injection and now 1000mcgs a day orally for about 10 years. I have had early signs of peripheral neuropathy for 10 years, and with a 5 generation family history of B12 deficiency realised adequate B12 could well be the problem. Sadly B12 is unlikely to reverse established neuropathy.
My neuropathy has, however, escalated dramatically since receiving the Covid vaccine and I am quite convinced from my reading of the scientific literature that the vaccine could well be the culprit.
I think that's likely. I only had foot numbness on occasion, before making the B12 connection, then numbness changed to burning toes and other symptoms kicked off after the spike jab. Too much of a coincidence to not be related.
Boy do I regret that decision, rushed into without my usual level of research and caution. I was that scared of getting the virus, especially after close family members really suffered with Long Covid.
The irony is that I was super careful, was virtually a recluse and didn't knowing contract it but I got really ill with B12D anyway 😭
My feet are hypersensitive all the time since the Covid vaccination and my feet and lower legs have a dreadful burning sensation, especially at night, which is bad enough to disturb my sleep.
This has been recognised as a side effect and it seems little can be done about it although gabapentin has been suggested as a treatment. I am reluctant to take this but if the problem persists I may be obliged to try it.
Atrial fibrillation and other cardiac issues have also been recognised as side effects of the vaccine. I am very lucky not to have experienced cardiac issues.
I posted my comment as doctors appear very reluctant to make the very obvious connection for fear of being branded as anti vaxx and disinformation spreaders. The MSM has also shied away from reporting adequately on the vaccine side effects presumably for similar reasons.
My fear is that under the proposed WHO pandemic proposals and the International Heath Regulations vaccination could be mandated by the WHO in any future pandemic and vaccine passports could become mandatory. These changes have never been properly debated in the UK Parliament but could become legally binding on the UK as they are currently drafted.
I would be extremely reluctant to have further mRNA vaccines because of my experience and my extensive reading in the subject.
I've had the vaccination and all the boosters offered. I have had no side effects. So far I haven't caught Covid. But I'm touching wood on that as I have to look after my mum and that involves socialising.
My AF is long standing, way before we had ever heard of Covid and is probably inherited from my dad (it's prevalent in his family) and my neuropathy began in my toes in November 2019 when my dad was in hospital for the last time. Again pre-Covid.
It’s a nightmare trying to work it all out isn’t it, especially when the medics don’t usually have a clue??!! But you have a good understanding of your thyroid & heart issues so can monitor it through heart rate, temp & do sometimes people check blood pressure too? I was thinking of the Paul Robinson info on signs & symptoms.
I haven’t heard of fluid retention being related to b12 deficiency but nothing would surprise me. It also may be related to your heart condition? 🤷♀️
Atrial fibrillation is an electrical conductivity issue with the heart beat, it's not heart disease so it should not be causing the fluid retention. I seem very susceptible to it where hormones are concerned. I had terrible trouble with it when I was trying to find my idea preparation and dose of HRT. And similarly along the way with thyroid. It happened all of a sudden this summer when I increased my Armour dose a small amount. But I needed that extra for energy. It may be that I have slightly too much T4 for my body now and might need to drop back the Armour a tiny bit and add in a small amount of pure T3. It is a nightmare.
Yes, blood pressure is another sign and is quite reliable for me to use. Much better than my heart rate.
Well as PA leads to low B12 and that in turn can lead to ectopic beats, it’s not a long stretch to think that for those with a predisposition low B12 might set AF off.
I get ectopic beats & palpitations occasionally but was never sure whether it was PA, Hashimoto’s or menopause causing it. My endo said he was ‘very relaxed’ about it!! 🥴
Check your potassium levels are good, b12 injections make a demand on potassium in the early days of treatment so it’s important to eat and drink the rda of potassium… also is your folate and iron levels good to support and utilise your injections?
I supplement iron and folate so they should be adequate at least. I will up my coconut water consumption for the potassium element. The last 2 bunches of bananas I've bought have been unpleasant. Weird texture. I've not been able to eat them. I have some more coming tonight from a different source so I hope they will be edible.
Although they have a persistent reputation for being high in potassium, Bananas have only 10% of the potassium RDA. On the other hand, they're an excellent B6 source with 20% of the RDA. So when you think of bananas, think of B6, not potassium 😁
The real potassium heavy hitters are legumes (beans, lentils), also avocado and spinach.
If you supplement large doses of iron every day this can paradoxically decrease absorption by increasing inflammation but usually this should only be an issue if you taking doses well over the RDA. Alternate day dosing seems to work better.
I'm not taking a high dose of iron. I should be OK. I have been too low still until after my last test when I increased the dose. What are the inflammation markers in a blood test? I will check my last one.
None of those foods are particularly regular in our diet. We have some, but not a lot. There is spinach waiting to be used now and we had beans last week. But no lentils for a while or avocado.
I am not medically trained but I believe C reactive protein is the most common marker for inflammation. If you're not taking large iron doses it is not likely to be a concern.
Coconut water is a good source.. jacket potatoes, avocados, tomato juice/paste sweet potatoes are a good source, legumes can be but best not eat too many as effects thyroid I believe
I don't think there's any reason to moderate legume intake for the sake of thyroid issues. There is little credible research indicating that to be necessary.
Hi Fancypants - I was diagnosed with B12 deficiency 3 years ago and self inject every other day because I have peripheral neuropathy. Last November I collapsed with severe vertigo and balance issues. Blood tests revealed TSH of 67- severe hypothyroidism. Now on 75 mcg which is probably right for my weight which less that 50kg. Feel a lot better than I did but not 100%. The 2 often go hand in hand. Chicken and egg. One more thing- you cannot overdose on B12, so don’t worry about that aspect
Yes, that latter point is reassuring. I need to get better at the injections though because so far they hurt and I'm only doing sub cut so I don't know what I'm doing wrong. Practice makes better I hope.
Do the injections help your peripheral neuropathy?
Not very much. I think I have had deficiency for too long but I feel much more energetic these days like I used to even though I’m 71. You just have to keep going and belong to thyroid forum as well as PA. The best support comes from fellow sufferers 😊
It has always been thus in the thyroid world. Doctors are hopeless mostly. Patients understand and experiment. I am so tired. Definitely more tired this week since starting the injections. I thought it was supposed to provide better energy! Everything I try tends to make me more tired.
What is the name of the thyroid forum? I thought this was it. You make it sound like there might be two. This one PA and another. If so, I'd like to find it.
You mentioned the injection being uncomfortable, so I went looking for a very old post I remember giving a full write up of how to avoid discomfort. I didn't manage to find the one I was looking for, but did find this thread that has a lot of discussion with members tips: healthunlocked.com/pasoc/po......
The injection hurts. The stuff is at room temperature anyway at the moment so it's no cold. I have tried twice to inject into my thigh, but it hurts so much I can't do it and have to use my stomach. That's less bad.
Most brands of hydroxycobalamin inc panpharma & that given by the NHS sting during &for a short time after injection. But it should only be temporary. If you use an alcohol wipe beforehand that can sting too (a tip from my b12 specialist). Pascoe doesn’t. Do you gently rub the area afterwards? That can help too.
I do rub it. It's not a sting if I try to do it in my thigh. it's like a needle of fire! I'll stick to the stomach area for now until I get better at it and then try my leg again.
So you mean the part where you plunge in B12? Mine would hurt at room temperature and I make sure it feels warm to the touch. Ampule under boob does job nicely ☺️
Yes. And last labs showed a TSH of 35.8, and my endocrinologist is you just need more hormones. Already on a crazy high amount. So mystery there. This thread is helping that.
My heart rate has been suddenly high since my thyroidectomy. But BP & heart rate due vary, for me, depending on what form of hormone I am taking.
Thanks for starting this thread, it has been very interesting & enlightening.
And high 20s on 150 Synthroid and 25 Cytomel combination.
Choices all over the place due to border issues & finances. Not my want.
Only one 'normal' lab @ 225 mcg Synthroid. But felt the worst of all hormones. Just awful. I am now wondering if I happened to be taking more b12 shots at the time. As I am hardly regimented the way I was at diagnosis. My fault for not keeping a diary.
Those who are new to either issue - I have sworn at myself many a time for not keeping a diary. It would have made everything so much easier.
Diaries are useful. But they make for sad reading over the years of constant struggle. You have weird TSH response to taking T3. So do I. What happens if you ignore it and adjust your dose on your FT3 result? I was at one point taking 60mcg T3 only and still had a TSH over 2 I think. Not normal. It could be that we have some sort of issue with the pituitary gland and so we should not be too hide bound by the TSH. It's so frustrating though. Whatever I do I never seem to feel any better. I'm so tired and weary at the moment. It's horrible. No life at all. Can't do any gardening or housework to speak of. I just sit around like a fat old lump of lard. It feels like I need more hormone. But if I try to raise it, I bet I suffer for it. Unless the B12 will allow me to raise with less issue. I'm longing for that to be the case.
Love sent to you FancyPants. Truly. I could read all your frustration so clearly. I am so very sorry you are going through so much.
The reason I mention the diary is this - I lost my legs through the b12 deficiency. Gait change, foot drops (no more drops since b12 supplementation) and just inability to walk properly more than ten steps without stopping. I was someone who lived in a downtown core and bounced around for hours and hours with glee, my whole life just before this period. I had sepsis twice during this period as well.
My legs never came back with the b12 shots. There is zero atrophy. That is what I say over and over to these medical professionals. That is a big hint - zero atrophy. That makes no sense. Common sense, sometimes I don't understand how they have little with years of education, shows it is a muscle quality issue and/or a receptor (brain) issue.
So the diary - twice I had moments of Hmm something is better and then gone again. I have to be careful to not link either moments to steroids, which I have had to take a few times. So another reason a diary would have made life easier.
But one time I had to do a ton of work where a diary would have taken seconds, the date was a loved one's birthday which made it somewhat easier & allowed me to investigate. Lucky. So I was able to figure out in time it was attached to t3 use. The reason I think it came and went was someone on the Thyroid board has educated me that these hormones come in directly where they are needed critically for that jolt but in time they are needed so many places and possibly too many places so to speak.
I went way off topic but back to your t3 statements/question. Unfortunately I have had to fight for T3 lab testing so it was left off too many times to have any clear picture of what you are talking about in your post. But one of the times I do have a good indication of 'that is so strange' when the reading was so low with 25 mcg direct liothyronine with 150 levothyroxine. I do not understand how 25 mcg was direct and t3 still not anywhere near 50% through the range. It is always low, when tested.
As far as the TSH, I agree. Something is wonky. My endocrinologist just sees it as 'more hormones needed'. I can't afford these constant increases. He thinks that because before him I had that one 'normal' lab @225 mcg Synthroid. But no reasoning that I am above the equivalency in NDT **&** nowhere close to a normal TSH, as that one lab. They just ignore that fact. And this thread might be part of that mystery.
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Well I have really gone on & on as usual, laughing.
FancyPants, tell me again what hormones you are on and what level. I am sure it is right in front of my face. But let me know regardless.
The first thing I want to say is that 25mcg of liothyronine is a small dose. I know doctors treat the stuff as if it were cocaine, but a full replacement dose for an adult on T3 only is between 60 and 75mcg a day. The NHS likes to make out 20mcg is the Holy Grail. It's not.
I'm currently on 2 & 1/2 grains of Armour. I will be doing a private blood test this coming week to see where my T3 is sitting in comparison with my T4 and then decide if I want to try an increase in NDT or if I want to add some pure T3 into the mix. I split my dose into 3. 1 grain at 8am, 1 grain at 4pm and 1/2 grain at midnight-1am. This stops me having to deal with highs and lows through the day. But I feel my best for the day around 5pm, so I suspect I need more in the morning and more at night. But of course I can only increase one at a time and then wait 6 more long weeks.
Hypothyroidism is a right pain in the arse and no doctor seems to understand it anymore or care about it/us.
Just want to be clear that that 25 mcg of liothyronine was not monotherapy, it was taken with 150 mcg Levothyroxine. So my t3 should have been a heck of a lot higher.
Will be very interested in hearing about your next lab & your decisions going forward. If you post and if you remember I would like to be alerted.
Hi, I have pernicious anemia and underactive thyroid. I’ve had underactive thyroid for about 26 years and PA for the last 10 years. I am not aware of any changes to the level of thyroxin needed due to starting B12 injections. My thyroxine has always remained the same at 100 mcg daily. I have B12 injections 8 weekly. Having the B12 injections hasn’t had any effect on the thyroid levels or the dose of thyroxine I take. I hope you find this helpful
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