Recently, I have been prescribed daily vitamin B12 tablets due to a low level of vitamin B12. It is thought that the low vitamin B12 is due to long term use (20 years) of metformin. Has anyone had a similar experience? How long should it take for my level of vitamin B12 to reach an acceptable level?
Vitamin B12
- Thread starter Olteanu
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The B vitamins are water soluble but they're a bit different from other water soluble vitamins. Normally excess amounts of water soluble vitamins are quickly expelled by your body because they're not stored, unlike fat soluble vitamins. But, the B group is a bit different because although they're not fat soluble they're stored in your liver. So, for a person not on medication the chances of a vitamin B12 deficiency is small (because the body stores it even though it's water soluble). That said, I do not know how metformin -- or other drugs for that matter -- might change this. It's known that other drugs can deplete B reserves so it's not unfeasible that metformin could do the same thing. A deficiency in B12 is not something I'd personally take lightly. As for how long it might take for levels to increase back to acceptable levels... no idea. Blood tests will tell you that, and that's something you need to do and do with your doctor. Don't ignore it though. There's no set time
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Yes, it is fairly common, and fairly well known that long term use of Metformin can (in some ppl) affect B12 absorption, leading to deficiency.
www.gov.uk
In an ideal world, this would be mentioned to the patient when they are prescribed the Metformin, and we would get regular tests to monitor levels, but we all know we don't live in an ideal world.
The length of time it will take to get your B12 levels back up to ideal, will depend entirely on how deficient you are, how much you supplement, and how much of that supplement your body can absorb and use.
www.medicalnewstoday.com
When taking B12 supplements, there are a few things that are useful to remember:
- don't worry about overdosing. Doctors can inject enormous doses of B12 to patients who are very deficient - amounts far in excess of any oral supplement doses. Any excess will just get widdled out.
pubmed.ncbi.nlm.nih.gov
www.mayoclinic.org
- if you are having problems absorbing B12 from food in the digestive tract (which is likely if Metformin is causing B12 deficiency), then you can get your dose is sublingually. This is where a dissolving tablet or spray is held under the tongue, and the B12 is absorbed directly through the thin 'skin' under the tongue and straight into the bloodstream, rather than from a swallowed tablet, which has to pass through the stomach and into the digestive tract, where it may or may not be absorbed by Metformin affected guts.
www.ncbi.nlm.nih.gov
- there are different forms of B12, and methylcobalamin is the most easily used (the most bioavailable) form. Of course it is also the most expensive form, and therefore unlikely to come 'free' on prescription.
ivboost.uk
It is very easy to source B12 supplements from any supermarket or pharmacy, but if you really want to get the best from your supplements, it is worth taking a little time and effort to source a sublingual version of methylcobalamin. I get mine from Amazon.
Metformin and reduced vitamin B12 levels: new advice for monitoring patients at risk
Decreased vitamin B12 levels, or vitamin B12 deficiency, is now considered to be a common side effect in patients on metformin treatment, especially in those receiving a higher dose or longer treatment duration and in those with existing risk factors. We are therefore advising checking vitamin...
In an ideal world, this would be mentioned to the patient when they are prescribed the Metformin, and we would get regular tests to monitor levels, but we all know we don't live in an ideal world.
The length of time it will take to get your B12 levels back up to ideal, will depend entirely on how deficient you are, how much you supplement, and how much of that supplement your body can absorb and use.
Vitamin B12 shots: Uses, benefits, and side effects
Vitamin B12 supports the health of blood and nerve cells, but some people's bodies are unable to absorb it. In this case, a doctor may recommend injections.
www.medicalnewstoday.com
When taking B12 supplements, there are a few things that are useful to remember:
- don't worry about overdosing. Doctors can inject enormous doses of B12 to patients who are very deficient - amounts far in excess of any oral supplement doses. Any excess will just get widdled out.
Vitamin B12 replacement therapy: how much is enough? - PubMed
Vitamin B12 deficiency becomes increasingly common with advancing age. Diverse recommendations exist for initial and maintenance therapy of deficiency states. With cyanocobalamin, the only B12 preparation available in the United States, much greater amounts of the vitamin are retained with a...
pubmed.ncbi.nlm.nih.gov
Vitamin B-12
Know the causes of a vitamin B-12 deficiency and when use of this supplement is recommended.
www.mayoclinic.org
- if you are having problems absorbing B12 from food in the digestive tract (which is likely if Metformin is causing B12 deficiency), then you can get your dose is sublingually. This is where a dissolving tablet or spray is held under the tongue, and the B12 is absorbed directly through the thin 'skin' under the tongue and straight into the bloodstream, rather than from a swallowed tablet, which has to pass through the stomach and into the digestive tract, where it may or may not be absorbed by Metformin affected guts.
Replacement therapy for vitamin B12 deficiency: comparison between the sublingual and oral route - PMC
To compare the efficacy of sublingual and oral administration of 500 µg of cobalamin in subjects with cobalamin deficiency. Thirty subjects with low serum concentrations of cobalamin participated in the study. Subjects were randomly allocated to ...
www.ncbi.nlm.nih.gov
- there are different forms of B12, and methylcobalamin is the most easily used (the most bioavailable) form. Of course it is also the most expensive form, and therefore unlikely to come 'free' on prescription.
The Four Types of Vitamin B12: Which One Is Right for You?
Learn about the four types of Vitamin B12, their benefits, and how they differ. Find out which type of B12 is best for your health.
ivboost.uk
It is very easy to source B12 supplements from any supermarket or pharmacy, but if you really want to get the best from your supplements, it is worth taking a little time and effort to source a sublingual version of methylcobalamin. I get mine from Amazon.
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