Worse after b12 injections: My husband... - Pernicious Anaemi...

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Worse after b12 injections


My husband has just finished 6 loading doses of b12. His blood result was 160 and apart from the injections no further tests were deemed necessary by gp. His symptoms were extreme tiredness and irregular heartbeat and recently unusual bowel activity. Since the 3rd injection he has suffered with bloating and dull ache in his stomach when he eats and his irregular heartbeat is more pronounced. He feels worse now that before injections, is this normal?

12 Replies
clivealiveForum Support

Hi Auntyp62 it is not uncommon to feel somewhat worse before getting better once B12 treatment has started.

It may be that your husband needs to supplement with folic acid and I suggest you ask his GP's advice on this,

I am not a medically trained person

I wish you both well

Auntyp62 in reply to clivealive

Thank you that does make sense to me

clivealiveForum Support in reply to Auntyp62

Your husband's doctor may not be aware of this

"Initially, replacing B12 will lead to a huge increase in the production of blood cells and platelets (which occurs in the bone marrow) and can lead to rapid depletion of folate and iron stores; this can then limit the expected recovery of Haemoglobin. Both iron and folate may be needed so please have these levels checked by your doctor".


Take care now

sbadd in reply to clivealive

Glad I read this, it explains where my iron went after loading doses

It can be unfortunately. Keep going back to the gp. Has h-pylori been tested and request full bloods. Including vit D and folate and ferritin. I'm astonished still that people arnt monitored . I've been going back as simply not better. A referral to a specialist may be necessary? Recovery seems slow for most people. Even though the doctor thinks you are cured after 6 injections!!

Also maybe get his potassium levels checked. If needed increase potassium risg foods..

Yes. Many of us have felt worse before feeling better. And it is slow. Check some of the posts on here for ways to try to alleviate digestive distress. If he has PA his stomach may no longer be functioning properly. Many of us use probiotics, lemon juice, other sources of acid and other digestive enzymes and diet changes to try to keep thing functioning as well as possible.

I had alternate injections for just over a month. 3 weeks if that was the worst I've ever felt in my life. Then my head cleared in a way that's very hard to describe , amazing is a word I could use but it wouldn't do it justice lol. Physically it's taken a good few months to start recovering from that initial , nightmarish , 3 weeks but I have run 18.5k and walked a further 11.5k this week so I'm feeling back to near my best. Ps I self inject 2 , or 3 , times a week determined by how I feel.

Thank you everyone, i have b12 def myself but never had his symptoms. We will try everything you suggest and then pester the gp if no improvement. I assume with nhs cost cutting, once b12 def is diagnosed gp feels no further testing to discover why as it’s easy for them to put right with injections. Then we are left with figuring out the underlying cause as that can still be a problem. Many thanks again

As far as I know (and somebody correct me if I am wrong) there are effectively just two causes of B12def; diet-related, and absorption-related.

The first can be treated by a change of diet, or oral supplements for those who won’t change their diet for doctrinaire reasons; the second only by injections.

Once it’s known to be an absorption problem, your husband could have tests to find out if the problem is IF antibodies destroying his Intrinsic Factor, or if the two inches or so of gut that absorbs the B12 is compromised, or whatever third or further factors there might be, but none are treatable as a separate thing, let alone curable.

So the treatment is the same, and for life; whatever injections he can get on the NHS, plus the very important management of iron and folate needed, and if he finds the NHS injections are too far apart, or not even forthcoming, self-management of the necessary intermediate top-ups (taps side of nose).

Mine has assumed to be linked to my Vitiligo as it has known strong link to b12 deficiency. I tested negative for IF. Am not aware of any other tests to assess the cause. My bloods showed low but in range b12 but the rest were fine.....good level of iron, blood cells normal shape

However over time regular b12 has transformed my neurological symptoms and I continue to improve a year on.

My hubby only really started to improve and feel better after his first maintenance dose when he was also given folic acid and vitamin d3. He was initially convinced the injections were red poison and everyone was trying to get rid of him!

Now he is going to ask for his next top-up at 8 weeks as he realises the difference it makes and that he was starting to slip back by the time 12 weeks were up! 🤞

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