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A 29-year-old member asked:

A blood test showed that i'm b12 deficient. serum b12 level of 186 pg/ml, should i take vitamin b12 supplements?

2 doctor answers8 doctors weighed in
Dr. Guy DaSilva
Endocrinology 36 years experience
Absolutely: B12 in the form of methyl cobalamin is necessary for numerous biochemical pathways. It can prevent psychoses, nerve tissue degeneration and megaloblastic anemia. Methyl B12 can be given safely at doses up to 3mg intramuscularly and can be given weekly in those patients who cannot absorb it through the GI tract. Otherwise, 2mg oraly is optimal. There are no known side-effects of having to much.
Dr. Richard Roberts
Pediatrics 47 years experience
Beware some OTC manufacturers who substitute the cheaper cyanocobalamin (a synthetic B12) which can not be absorbed by the mucous membranes. You need the biologically active form, methyl cobalamin (also called Mecobalamin), which is readily absorbed through the mucous membranes.
Oct 10, 2015
Dr. Eric Weisman
Neurology 37 years experience
B12: this low will likely cause dementia, spinal cord degeneration and peripheral neuropathy. Keep your level above 550 for the rest of your life. Recovery takes about a year in a young person. I suggest you take liquid sublingual weekly for 3 months then bi weekly thereafter. Its important to check a level after you cut back to twice a month. Use 1 1/2 dropper and hold it under the tongue for 30 sec.
Dr. Richard Roberts
Pediatrics 47 years experience
Beware some OTC manufacturers who substitute the cheaper cyanocobalamin (a synthetic B12) which can not be absorbed by the mucous membranes. You need the biologically active form, methylcobalamin (also called Mecobalamin), which is readily absorbed through the mucous membranes.
Oct 10, 2015

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