Pernicious Anaemia Society
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Bit off topic! Am on b12 inj, now diag with hypothyroid and looking at iodine/ adrenal testing, any advice on tests for these please?


I've recently been advised to take thyroid treatment, as well as my monthly b12 injections as the dr believes my thyroid levels could be affecting the absorption of the b12 and the symptoms wouldn't reappear as quickly.

I'm concerned at starting this as I'm worried the b12 def may be causing stress on my thyroid, so have been reading about the benefits of iodine and adrenal testing (because I'm underweight, rather than the usual overweight of hypothyroidism and read adrenal issues can be the cause of this and it can be dangerous to take thyroid meds without correcting first)

I've found various tests and although have undertaken adrenal testing before, haven't done a iodine test.

Wondering if anyone has and whether the urine or pinprick are more beneficial please? Neither involve taking an iodine supplement first. Can see a good offer on over Bank hol weekend, but unsure whether a preference between the urine or blood for iodine.

Any help gratefully received thank you.

6 Replies

Hi Jo5454. Sorry, can't help with this one but I see you've posted on the thyroid forum and had an answer there.

Your GP may not be aware, but the symptoms of B12 deficency can reappear very quickly after an injection...some people need to inject every other day to get and remain well...especially if neurological,symptoms are present (in which case, the B12 regime is every other day injections until no further improvement). may well be having the symtpoms of B12 deficency bra use [auto correct error- read as because - though bra more entertaining 😆] you need more frequent injections.

But its complicated because of the cross-over symptoms between hypothyroidism and B12 deficency (and other things too - iron deficency, for one). Your TSH is high so it may be that you have a complex mix of symptoms from the two different conditions - which should be treated simultaneously.

Note - think hypothyroidism can also cause problems like weight loss to - but best check this against the symptom list on the thyroid forum or post a question there.

If there's any likelihood that your symptoms are due to B12 deficiency (and it possible they might be) then your doctor should try increasing the frequency of your B12 injections to see if this effects symptom relief. (Withholding B12 in the mistaken belief that symtpoms cannot return has the potential to cause irreversible neurological damage if that's what the underlying cause is - and the only way to be sure is to try more B12 😄).

Also - has your GP checked your folate levels? B12 and folate work together so if your folate levels are deficent or low the body cannot utilise B12 properly - and you get the (very similar) symptoms of both B12 and folate deficiency. Ask your GP to check your folate levels if these have not been done.

Just a endocrinologist did a whole range of thryroid, adrenal, parathyroid and pituitary tests (much more than can be done via individual private blood tests).

So a second thought...if you're seeing an endocrinologist for your thyroid issues, explain your concerns about potential underlying health issues and they can arrange testing for you.

And if your not seeing an Endocrinologist already, ask your GP to refer you - especially if you're having trouble getting your symptoms under control. (which may be hypo, or B12 released - or a mixture of both 😖). Would be the usual course of action so it would be appropriate for you to ask.

A last thought...many GP's won't accept private blood results and simply arrange for them to be done could always ask your GP for the test (and cut out the paying bit).

Think I'd try and go for the endocrinologist option - get your thyroid sorted and get the other screening tests done too 😄.

Sorry I couldn't answer your question 🙃

Good luck

P.s. Not sure how much you know about B12 deficiency so here's some links to information and guidance at may help - looks like a lot but most are only one page long. Post again if you need more's the links....

b12researchgroup.wordpress.... (Serious Caution Note about the use of Oral and Sublingual B12 Supplements) (BNF B12 Deficiency: Hydroxocobalamin Treatment Regimes)

pernicious-anaemia-society.... (PAS Symptom Checklist) (BSH B12 Deficiency / PA Diagnostic Flowchart) (British Society Haematology (BSH) Guidelines: Treatment of B12 Deficiency and Folate Disorders) (NICE Guidelines Treatment of B12 / Folate Deficiencies) (UKNEQAS B12 Treatment Alert, Neurological Symptoms and Risk of Subacute Combined Degeneration of the Spinal Cord) (Problems with Serum B12 Test) (Testing B12 During Treatment) (Misconceptions About B12 Deficiency – Good to Know Before Seeing GP) (B12 Treatment Safety / Long Term Treatment for neurological symptoms) (B12 Deficiency: Neurological Symptoms Can Present Even When B12 is ‘In-Range’ and Without Macrocytosis (large red blood cells) or confirmed PA Diagnosis) (B12 and Intrinsic Factor) (B12 & Nitrous Oxide Contraindicated)



Hi Foggyme,

What's a B12 deficiency bra?

Do you think I could get one of them?Might do me good, might do us all good, fbirder & clivealive included of course.



Hi Jose651. LOL. LOL. Think this is a case of being well supported by HU autocorrect 😀.

Think I'm going to leave it as is - might cause a bit of well needed laughter 😀😀.

Certainly got me chuckling out loud...



Thank you so much for taking the time to write all this information and so sorry it's taken so long for me to thank you.

My dr won't increase the b12 injections so the only option there is to try some tablets I guess. He's not keen to refer me to a neurologist in case this effects the injections and I can't have them as regularly? I had to do a postal test privately to get the functional b12 def diagnosed, bit of a battle! :)

I'm going to have to try something as am feeling rotten , it's just strange that I had been noticing more of a difference after the injections, but since taking a few courses of antibiotics prior to Christmas (unfortunately shouldn't have taken them with a b12 def) it doesn't seem to be working as well and I'm struggling to find any energy, but it's so difficult to try and separate the symptoms from a potential thyroid prob too, but as you say I have to try more b12 to see.

I asked whether I need a scan when dr suggested thyroxine, but said it wasn't necessary, but I can get back and ask to be referred to an endocrinologist. Did you start treatment before you saw yours please?

I've done an adrenal test and iodine urine as a starting point yesterday, but appreciate what you're saying that I'd get much more via NHS so will ask about that too.

Think I'll also try and boost myself with some folate and extra b vits.

Thanks so much for all of those links, will work my way through them...

Loved the b12 bra thought!:) bring on the day of such an invention,lol!

Was doing one of the saliva tests yesterday and filled the tube up when I realised the numbers were on the other end. So tipped it out and and filled the other end of the tube. Then realised there wasn't a screw top that end to place the lid and that I was right the first time and it was them printed the label space and ml guide the wrong ends, so third time lucky tipped it out and refilled other end,lol! roll on the next jab!

Thanks again and good luck with your health...:)


Hi Jo5454. In answer to your question, no I did'nt start treatment before I saw the endocrinologist (assume you mean thyroid here). Awaiting next appointment, so we'll see.

Think your GP is wrong about the referral to a neurologist...if you have unexplained neurological symptoms (unexplained because your GP is assuming they are not down to B12 deficency), then further investigation should take place - via a neurologist - to rule out underlying causes.

Consultants only can only offer advice to GP's, which they are under no obligation (sometimes unfortunately) to follow so...there is no reason why your GP should change your current frequency of B12 injections if he/she doesn't want to...and on that issue (assuming you're in the UK)...

When B12 deficiency presents with neurological symptoms, the B12 treatment regime, following loading doses, is every other day injections until no further improvement - for some this can take many months. Many GP's are not aware of this regime (see BSH and BNF guidelines in the links above). Your request for more frequent injections is in line with UK guidelines and there is a risk that under treatment of B12 deficency could possibly cause irreversible neurological damage (not saying this to frighten you...more so to give your the courage to re-approach your GP for more frequent B12 injections (as per the neurological regime). You can use information from the links above as evidence to support your request for more frequent injections - print the documents and highlight the relevant bits so your GP can scan quickly - most don't have time to read everything 😖.

Good luck, hope you find some solutions soon x


Thanks so much foggyme. IT was a battle to get b12 def recognised and I tried really hard to get the injections for more than 2 weeks initially, but had no luck and was too ill to fight any further. By the 6th one I felt they were starting to work and was desperate to keep going. I was told if if I was having problems with alcohol then I'd be considered!

Thanks for info about neurologist and endocrinologist. Not sure which of these routes I should go down next really! I am going to make sure I'm taking everything I should be to support the b12 too...

I hope your next appointment goes well and you've found an understanding dr to help...thanks again x

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