do all otc b12 injections give you acne Break outs after course : r/B12_Deficiency Can B12 Vitamins Cause Acne?
Description
During the procedure you may experience sensations of pulling, tugging, mild pinching, intense cold, tingling, stinging, aching, cramping and discomfort at the treatment site

In severe cases 1 ampoule daily until the acute symptoms subside

Using medication significantly past expiration is inadvisable
The 3.0 mL dilution gives a clean 4 mg/mL solution where 1 unit = 40 mcg, keeping the math simple across the titration