How low B12 is tested for Confirming a B12 problem starts with a serum B12 blood test
Apart from red-colored urine (in case of intravenous administration), innocent skin discoloration, and possible soft stools, no side effects have been reported at the intervention evaluation
However, for exceptionally thin or muscular people with little subcutaneous fat, you may need to insert the needle at a 45-degree angle (diagonally) to avoid injecting it into muscle tissue
This is a veterinary product for use in animals only
For addressing a deficiency or supporting weight loss, we typically recommend weekly or bi-weekly injections
However, as described below, there doesnt seem to be a benefit for neurological problems in going beyond the amount of B12 generally recommended by the EFSA