Has anyone seen or can recommend a haematologist in the uk that understands b12 deficiency or functional b12 deficiency. My GP says his hands are tied.

He referred me to haematology who said he didn’t a good understanding of a b12 deficiency and to ask my Gp to find some that has a special interest.

GP says he doesn’t have time, yet if I find someone he will refer me. I feel I’ve got more chance of finding a golden unicorn.

If anyone has any suggestions I would be extremely grateful.
Many thanks x

My b12 level is 109 . So doctor prescribed me mythlecobolamin 1500 mcg for one months. I don't show any effective result. So Now doctor prescribed me b12 shot for continuously for 5 day then one shot in a week for a months. My symptoms are barinfog and headache so what do you think after how many day I get relief

I'm pretty sure I've been b12 deficient for like 5 years and I have become so accustomed to it that I am losing my mind when I try to correct it. It is too the point I almost want to stop taking it and just let it continue doing the damage because it is genuinely such a horrible feeling to go through trying to correct the deficiency. Last night before I went to sleep I felt chills down my spine, it was like I could feel the blood running through my spine. Then I just started absolutely freaking out. I felt really cold, and I felt tingling like inside of my head and I kept having random childhood memories running through my hea . And I had sharp back pain on my right side, but it kind of went away when I felt the flush of blood running through my back. It was a genuinely insane experience. I was like 100% sure I was going to die, but I just got some extremely broken sleep where I was like basically dreaming while I was awake and I was profusely sweating all night. It was honestly traumatizing, but like I genuinely feel better today despite literally being traumatized by what happened. I think my brain is a lot clearer today, but I am still quite shaken up by what happened yesterday. Maybe this really is a sign to stop taking it or that b12 really isn't the issue, but this is just fucking insane. I think I'm becoming schizophrenic or something

It’s become a straight disability. I can taste everything i smell. It’s caused me to avoid places because i have to frequently brush my teeth to get it out.

Hi folks. I'm trying to fine-tune my supplements. I'm getting a rash when I take my meds, and I think B6 is the cause.

About 15 mins after taking tbe handful of pills that constitute my breakfast, I developed a very bright and hot rash on my face, chest, arms, and knees. It took about 30 minutes to go away. I had some stomach discomfort, nausea, anxiety, heartrate increase.

In looking into this further (thanks /r/MCAS), I'm pretty certain B6 is the cause. I've seen a range of recommended doses on this forum, depending on the stage of deficiency management, and while I was at one point B6 deficient, I worry that I'm overdoing it right now.

I'm going to be excluding B6 tomorrow, but I'm hesitant to take it again because the flush was very fast and severe, and I'm a little worried about anaphalaxis.

Have you experienced anything similar? How much B6 do you take per day? Any recommendations for stopping or lowering my dose?

I'm taking the following:

- daily cyanocobalamin, 1000mcg

- C - 500mg

- D - 240mg

- Zinc - 100mg

- copper - 5mg

- selenium - I forget. Just one pill, 100% rda

- omega 3 (fish oil)

- b complex

- b6 (100mg)

- magnesium, 400mg

- potassium (chloride, as needed, basically in all water)

- (Edit to add) iron, 65mg EOD

I'm not at home so can't check the exact amounts, but I do know b6 is right because I've worried about it a few times

1 month ago my b12 was 391 and homocysteine 18.4. I began a oral supplement called Homocysteine Nutrients but the methyl b’s proved too stimulating for me. Ive been taking now 3-4 5mg cyanocobalamin tablets each day for 3 weeks now. I responded very well at first but the mood/cognitive improvements have faded. Initially, after eating or exercise I felt short of breath which I read could be a potassium deficiency due to b12 intake. So, ive been trying to get in 2g of potassium a day. This feeling has faded. Exercise does leave me worse off than before, I feel incredibly brain fogged, numb, and anxious after, usually getting a hypnic jerk or two that night before falling asleep.

1 week ago I received a methylcobalamin injection from my PCP and well Im not sure that did me good mentally. For the past week ive been feeling “out of it”, like nothing I am perceiving is how it should be or felt before, or I am getting memories of past times where I have felt this feeling (false perception if memories?), and general anhedonia for activities I usually enjoy (work, video games, music). I will be honest I felt this before the methyl injection but now it is worse and still feels worse 1 week later. Other symptoms like tinnitus, tingling, lighting feelings are back a little bit too.

Has anyone else experienced this?

Edit: also, Ive been experiencing some hair shedding

34M, moderate smoker.

Since Nov 2025, after taking metoclopramide + fluoxetine, I had what felt like a panic-like episode. Shortly after that, I started developing symptoms that have not fully resolved.

Main symptoms:

• Persistent or recurrent retrosternal squeezing/pressure-like chest pain
• Occasional electric shock-like sensation in the left chest
• Dull discomfort in the jaw/teeth area (no dental cause found)
• Jaw sometimes feels mildly tender when touched
• Symptoms occur both at rest and during exertion
• Chronic symptoms without full remission
• No shortness of breath, nausea, dizziness, or sweating

The chest sensation feels more like angina-type discomfort than a typical panic attack.

Mental health / medication background:

After the initial episode in November 2025, I switched from fluoxetine to escitalopram, and also used a short course of benzodiazepines because fluoxetine was suspected to be too activating.

Following this change, I felt noticeably better for about 1–2 weeks.

However, in December 2025, I suddenly developed a stronger episode of retrosternal squeezing chest pain, which triggered significant fear and panic. Since then, the chest pressure has persisted as part of the ongoing symptoms.

I am also currently being treated for panic/anxiety disorder with escitalopram.

Even with my history of anxiety, I have never experienced symptoms like this before, which is why I’m confused about the cause.

Cardiac workup:

• Resting ECG: normal
• Echocardiogram: normal
• Exercise stress test: achieved 12.4 METs, interpreted by the cardiologist as clinically and electrically normal, with no ischemia and no symptom reproduction
• Blood tests including troponin: normal

➡️ Overall, cardiac causes were considered very unlikely.

Gastroenterology workup (endoscopy):

• Grade 1 sliding hiatal hernia
• Distal esophageal erythema / reflux esophagitis
• Mild chronic gastritis
• H. pylori infection (currently under eradication treatment)

Current issue:

Despite treatment, I still experience persistent retrosternal chest pressure and dull jaw discomfort, and I’m struggling to understand what is causing it.

Possible explanations I’ve considered:

• GERD / reflux-related non-cardiac chest pain
• Hiatal hernia–related discomfort
• Esophageal hypersensitivity or spasm
• Musculoskeletal chest wall pain
• Referred or nerve-related pain affecting the jaw area
• Anxiety/stress amplifying physical symptoms

Main question:

What could explain this combination of:

• retrosternal squeezing chest pressure
• dull jaw discomfort
• normal cardiac workup (including stress test and troponin)
• mild but real GI findings
• absence of classic cardiac-associated symptoms
• and symptoms that feel very different from my usual panic/anxiety episodes?

Has anyone experienced something similar or found an explanation for this kind of symptom pattern?

Hi. I (female 45) have a history of very low B12. First instance was in 2019 and a level of 58 ng/l 😬 and again in late 2023 with 95 ng/l. This was, in the first instance, dietary (vegetarian for 30+ years) and in the second occurrence, careless on my part. I accept full responsibility for it. Intrinsic factor negative. I felt no better in either case after loading shots, maintenance dosing (12 months) and b12 and folate supplements. Typical presentation of fatigue, weakness, breathlessness, tinnitus, cog fog (at one point couldn’t remember how to change bed linen), lack of co ordination, balance issues, weird sensations in limbs, headaches, memory issues etc. GP dismissed this as anxiety and depression when I explained I was still feeling terrible after several months. B12 levels were 1400+ with high folate.

Managed b12 with high dose oral supplements once shots were stopped after allergic reaction towards the end of loading (2023). B12 levels found to be 1300+ with high folate.

Fast forward to March this year. Seen by neurology for tremor and balance issues . Still experiencing neurological symptoms (as above with some extras thrown in) but not asked about anything other than tremor. Bloods taken with B12 levels of 1019, folate and ferritin on the lower end of normal so have started with a higher dose of those and have also added in vitamins c&d.
I told the neurologist that I was aware that very low b12 can cause irreversible neurological damage and that I was concerned about it. This wasn’t addressed or even acknowledged and she proceeded with a diagnosis relating to tremor only.

Been to see my GP this week. I brought it up with them and they told me that neurological symptoms of b12 deficiency would have resolved quickly after therapy. From researching, I don’t believe that to always be correct in cases of prolonged and severe deficiency. Surely levels of 58 would have to be prolonged deficiency (clearly didn’t drop that low overnight) and I would think severe
. The symptoms have never gone away or improved.

Thoughts? Clutching at straws? Please and thank you.

* I am not looking for anything to be wrong. I would like to understand why I feel like this and hopefully find a way to improve*

I only just found out I am B12 deficient and am so grateful for this subreddit. Friday I started to feel extreme burning in my stomach and acid reflux, that night I completely lost my appetite and it hasn't returned since. I've had numbness in my stomach, back and chest. I started injections on Saturday and had my second on Tuesday. I'm going again tomorrow for another. I have been going to pharmacies and two different doctors to do this as they will only give me one weekly. All other symptoms such as neck pain, trouble swallowing, brain fog and insomnia have begun to improve but my appetite is still non-existent. I am struggling to eat 3000kjs a day and am losing weight rapidly, I am also only interested in liquids such as up and go's and soup. Has anyone else experienced this and know a timeline? Or have any advice? I've bought supplies to start injecting just in case I can't get a doctor to prescribe and I am having hydrolight for potassium and a B complex multivitamin.

I'm getting a lot of wake up symptoms. Please share what experiences you went though waking up.

I have had b12 bloods and they’ve been fine. But I’m wondering if anyone else has had this and benefitted from a b12 supplement nonetheless. I can’t get shots for this reason as they don’t see the need.

I have a lot of symptoms that could be b12 deficiency and wondered if it’s worth just using vitamins. Feels difficult to find some thing that is good / will be absorbed

Background: I recently found out that a long list of symptoms can be explained by B12 and iron deficiency. I'd love some guidance around how to explore this with the nhs or otherwise...

Symptoms (the classics): fatigue, brain fog, breathlessness, hair loss, nail ridges, low mood, anxiety, extreme post-exercise exhaustion, energy crashes after eating.

The numbers

• Active B12: 56.7 pmol/L
• Ferritin: 23 (was 16 in March, NHS marked it normal, no action 🙃)
• Haemoglobin: 117 (was 112 in March, NHS also marked as normal, no action)
• have lots of other numbers but not sure which are relevant! (I'm trying to work my way through the b12 guidance doc but I won't lie, the brain fog and fatigue are making that slow work atm)

Why I don't think it's dietary

I eat a varied whole foods diet, meat, fish, dairy, eggs. I'm currently taking a B12 spray while I investigate further...

GP appointment Tuesday: I'm going to ask for the following

Tests for underlying causes:

• Intrinsic factor antibodies
• Gastric parietal cell antibodies
• Coeliac serology
• H. pylori stool antigen test
• FIT test (an iron infusion consultation asked me a question about blood in stool and now I'm retrospectively thinking I do...)

Treatment:

• I'm going to ask for the B12 injections straight away whilst we investigate the source.

Questions for this community

• Should I be asking for any other tests?
• Will I get resistance to getting the injection while we investigate? What should I be pushing for?
• Best route to unbiased holistic advice. Should I be trying to get a referral to a haematologist?

Thank you so much for being such a welcoming and active community (that we all wish we weren't a member of haha)

Comentem aqui

43M - UK

At the end of last year I started experiencing some alarming symptoms. Mostly relentless, loud tinnitus, dizzyness, brain fog, headaches, lethargy particularly after eating, coupled with tight chest and the occasional heart palpitations. I put this down to work stress, at the time I had fairly frequent international travel and project deliverables. I have also suffered from back-to-back frozen shoulders - quite uncomfortable and quality of life affecting.

What seemed to be consistently happening was any cognitive load would manifest as tight chest / pains and excessive tinnitus. My body would react excessively stressed to something as simple as driving my car.

This dissipated somewhat but come April this year the symptoms returned with a vengeance and I sought medical help. I felt like I couldn't work any more (I'm a software guy so cognitive decline really worried me), and this had a self-reinforcing effect: anxiety about my inability to work increased my stress, which affected my health, and vice-versa. I felt frequent chest pains and tight chests until one day at work I called NHS 111 and they sent an ambulance to check me out just to be safe and I spent the evening in A&E. I had experienced severe chest tightness, pains, sweaty palms and huge anxiety / disorientation. Most likely a panic attack which I have never had before.

In short, I was feeling like my body was falling apart across a multitude of areas.

Just a week prior to this I was diagnosed with a B12 deficiency and started taking supplements (B12 "dual power" (with methylcobalamin) - I'm sure others are equally effective). I started reading this subreddit and I thought... wow.. could this actually all be down to a B12 deficiency?

Here's my timeline:

21st April: 134ng/l / (99 pmol/L)
23rd April: Started taking B12 supplements
27th April: 148ng/L (109 pmol/L)
30th April: Ambulance called - precautionary due to heart / chest pains.
Early May: Vacation and gradually improving health.
13th May: 189ng/L (139 pmol/l)

I'm not fully recovered, stress is still present but my day-to-day disorientation has completely gone with some light tinnitus remaining. The change has been remarkable, to the point I'm not completely convinced it was entirely B12 - I think my poor health was a B12 deficiency and general life stress compounded.

I've really gained a new found respect for people genuinely experiencing "mental health issues". It was inconceivable to me; my brain rationally explained my issues and consciously I didn't feel too stressed, but my nervous system was just completely shot and would react in fight-of-flight mode on the most insignificant stressor.

On a personal / private level my libido had *completely* disappeared leading up to, and during this. And now? .... let's just say I'm waking up with morning vigor again these days! ;)

I hope this little diary helps or relates to someone. This subreddit has been genuinely a helpful place to come to. Thank you all!

Edit: removed the brand name so this doesn't read like a trojan advert

i have heard you have to stop supplements for 3+ months before getting tested to have an accurate result..
first- is this true? second- is there another test i could do where this won’t be a problem… i have to drink boost plus shakes daily bc im very underweight but they have b12 in them

I have had bloating and treatment resistant SIBO, slow motility and hard stools. Also fatigue.

I have been testing and trying every therapy for SIBO. I did a 2 week elemental diet. Bloating did not reduce.

I recalled a long time ago, as part of mental health work up, I had the methyl gene tested and it was positive for something

So I asked doc for homocysteine test and it was... Slightly elevated?

Reading of 23, reference range normal is less than 15. Is that high ? Note however this was with a few days of supplementing activated b12 before the blood draw because I didn't want to wait.

Does this mean I need b12 shots ? Or sublingual is ok?

When can I expect my gut to feel better.

After just a few days of b12 I feel...like my stress response is a bit elevated, not very comfy, is that normal

So. LabCorp version of this is a joke. Does anyone have the brand & test name of something that will show a serious amount of information even under heavy IM B12 supplementation? And are any tests you can get at local clinics in the US? I have even heard of mail-away tests, but can’t imagine they’re super accurate…

I’m exhausted doing tese tests one or two at a time n not getting the whole picture.

But thinking I’m obviously deficient in some other nutrient(s), because eating 3.5oz or so of beef liver every week makes the physical symptoms just disappear. Feel almost ‘normal’ for hours and hours…sometimes into the next morning if late enough (though try to eat it b4 2p, bc it’s so nutrient-dense it makes me hyper for a while after).

Anyway. Any tips n research n anecdotes WRT actually informative comprehensive tests MUCH APPRECIATED!!

TYVM,

SDH

I went in for a check up due to feeling a bunch of the usual symptoms. B12 was at 301, which was down by 70 from last years results. Nurse tells me its within range and my blood work looks perfect. A couple weeks later, I did a follow up blood test with some additional tests associated with low b12 and they all seem to be fine despite my b12 dropping even more (down to 265). Here are my latest results. I only listed what I thought was relevant since the list is long.

• PARIETAL CELL AB, ELISA: <=20.0
• INTRINSIC FACTOR BLOCKING ANTIBODY: Negative
• METHYLMALONIC ACID: 106
• HOMOCYSTEINE: 13
• Potassium: 4.0
• Iron: 141
• Ferritin: 50
• TSH W/REFLEX TO FT4: 1.2
• B12: 265
• D: 41
• WBC: 4.4
• RBC: 4.8

Any reasons why my B12 is dropping? Are there any other tests I should get done? I don't have a diet restriction, I'm not on any medication, I have an active life style.