Antibiotics and infection: how much d... - Pernicious Anaemi...

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Antibiotics and infection: how much do these deplete b12 levels?


I am currently finishing up 7 days of oral antibiotic along with 3 days of IV antibiotics for an infected hand. I started to “feel funny” on day 2 of the IV antibiotics. Fatigue, randomly short of breath, clicking when I swallow, some anxiety....all symptoms that had disappeared a few months after starting b12 injections. Anyone else experience this with antibiotics or a severe infection? I have read that they can can also deplete iron, magnesium etc.

Just when I finally had things under control😣. Hope everyone is doing well!

9 Replies

not sure that anti-biotics deplete B12 levels but they may interfere with the metabolism of B12.

It is known that anti-biotics can cause mild depression but not clear if the causal link has been identified and it could be nothing to do with B12

Sorry - but can't remember which anti-biotics are known to potentially interact badly with B12 - you could try asking a pharmacist.

I was prescribed Zantac for gastric/digestive problems for years as well as strong antibiotics each time I had dental treatment (leaky heart valve) and again as treatment for H/pylori.

Although I'd been managing on high dose B12 sublinguals, I found myself having to begin self injecting Hydroxocobalamin every other day after two viruses led to the onset of neurological problems (crippling fatigue, dizziness, memory problems, pins and needles etc.) It has taken eighteen months of SI as well as other nutrient supplementation, probiotics, etc. to recover health.

Although antibiotics are obviously vital to fight serious infection, I believe these and other substances gradually undermined B12 absorption over many years:

Plucky11966 in reply to Polaris

The funny thing is I NEVER take antibiotics. I had no choice this time around so I’m now wondering if the healing of this infection before I started taking antibiotics just used up much of my stores?

Polaris in reply to Plucky11966

That's the conclusion I came to after having the viruses, Plucky.

Interestingly, this popped into my inbox yesterday. Made me wonder about the connection and what would have happened had I not started s.i. B12

Long term use of some antibiotics can hinder absorption of B12. But, if you’re injecting then it should have no effect.

I’ve found that a viral infection can exacerbate the symptoms that are normally hidden in the background. But only for the 7 to 10 days the infection lasts.

Plucky11966 in reply to fbirder

Today is my last dose somy fingers are crossed!

It depends on what antibiotic you are on - just like us, different ones work in different ways.

Trimethoprim is known to cause significant problems with folate and as folate is required to make your B12 work properly (as well as giving similar deficiency symptoms) you can get problems with this.

As well as reading the package leaflet you could look it up online to see if anyone else has had a similar problem. There is a Yellow Card system for reporting additional side effects to medicines and it would be good register your problems for the future benefits of others.

My symptoms flare with viruses or any stress really.

I guess that just means I will need to up my frequency of injections during these times.

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