Question

How much vitamin b12 injection should be taken at a time?

Answer 1

doctor may prescribe vitamin B12 injections if you have low levels of B12 in your blood, a condition known as vitamin B12 deficiency. B12 deficiency can result if you don't eat enough of certain foods, particularly meat, poultry and seafood, or if you have an inability to absorb vitamin B12 from food. If your B12 absorption is impaired, you will need to receive injections more frequently than you will if your deficiency is a result of an inadequate diet.

Answer 2

People with this deficiency are likely to have or develop symptoms. Older adults with vitamin B12 levels between 200 and 500 pg/mL may also have symptoms. Deficiency should be confirmed by checking the level of a substance in the blood called methylmalonic acid.
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