Pernicious Anaemia Society
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B12 test

I have pernicious anaemia. I didn't know I was being tested for it but I have injections every three months. I have tinnitus constantly and get very tired before my injection is due.

My mum has Alzheimer's and I was surprised to read on this site about B12 and memory loss. Do you think I should get my mum checked for B12 deficiency, I am the only member of my family with this.

7 Replies

Yes, I would if it was my mother. A B12 deficiency plays havoc with our thought processes.


Has your mother actually had a diagnosis of alzheimer's or is alzheimers being used as a 'catch-all' for dementia?

Alzheimer's in the strict sense has specific chemical markers and tends to affect the hippocampus first - meaning anxiety and depression tend to be key characteristics. It is also quite rare that onset starts after 65. It is different from the 'dementia' caused by B12 though there can be a significant overlap in the symptoms.

As you get older levels of acidity in the gut start to drop and this is one cause of a vitamin B12 deficiency. At 51 at least 3% of population will have a B12 deficiency and this percentage rises with increasing age so, yes, it is always worth checking that B12 isn't going on as symptoms are often mistaken for aging until they come very advanced - at which point some of the damage is likely to have become permanent.

Generally the window for treating brain damage caused by B12 (shows up as lessions in the brain - making it more akin to vascular dementia) is thought to be about 6 months - at which point B12 treatment will stop things progressing but won't be able to reverse damage that has already been done.

This is a link to the symptoms of B12 deficiency as your mother will probably be showing other symptoms by now if B12 is involved. A lot of the drugs used to treat the other symptoms can actually make absorption problems worse meaning that symptoms start to develop thick and fast.



Hi, thanks for your reply.

Mum does have Alzheimer's and when we saw the doctor on Friday she thinks we need to think about a home because my dad is 84, and my mum is becoming a danger to herself and him.

I never thought about getting her b12 checked, I have been having injections for 2yrs. I will call her doctor. I know there's no cure but I will give anything a go to slow things down.


Diane, I have recently been diagnosed with PA and as far as I know I am the only member of my family with it. My mum has Vascular Dementia, as far as I am aware this was caused by a mild stroke. She has her bloods checked regularly and her B12 was fine but was deficient in Iron. You may need to get your B12 injections every 2 months. I also have tinnitus and other symptoms, my B12 injections do not put these away. I may have nerve damage. Good luck with everything. Nic

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"I have injections every three months. I have tinnitus constantly "

Tinnitus is a neurological symptom. Do you have other neurological symptoms?


The treatment for those with B12 deficiency with neurological symptoms is more intensive than you are receiving. For those with B12 defic and neuro symptoms there is a small window of opportunity to improve things before there is a risk of neuro damage becoming permanent.

Info on correct treatment is in the BNF (British national formulary) Chapter 9 Section 1.2. All GPs will have access to a copy of BNF. I think that those with B12 defic and neuro symptoms are supposed to have an injection every two days until they stop improving (this might mean loading doses over a period of weeks or even months) then an injection every two months. How many loading doses did you receive?

You may find it helpful to ring the PAS. If you leave a message they will get back to you.

pernicious-anaemia-society.... 01656 769467

Other useful info

Google "BSCH Cobalamin and Folate Guidelines"

Could It Be B12 by Sally Pacholok

Pernicious Anaemia; The Forgotten Disease by Martyn Hooper

Living with Pernicious Anaemia by Martyn Hooper

If you search for other posts I have written there may be more info on those.

I have a relative with dementia and wonder about B12 deficiency too.

Good luck.


The book by Sally Pacholok says the gray zone for B12 is 200 - 450 pg/mL, which is where neurological damage can occur. This includes brain problems that include memory issues and dementia symptoms as well as numbness and pain in the extremities. Many doctors in the UK and US are using a low cutoff of 200 or even lower. If your mother's B12 is in the gray area you may need to push her doctor for treatment or switch to another doctor who will treat her.

There are some PA sufferers who self-inject or use supplements between doses.


Thank you.

I am going to contact my mums doctor today.

If she won't help I will go and get b12 tabs they won't hurt her,so will give them a try.

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