vitamin b12 injection site Sites — Raleigh Botox Choosing the Right Needle and
Description
(the New York Times) - behind the Headlines - NLM. NCBI, www.ncbi.nlm.nih.gov/search/research-news/8501/

Easy measuring: At ~0.667 mg/mL, 1 unit 6.67 mcg on a U-100 syringe, so 300 mcg 45 units and 500 mcg 75 units

Amino acids are the building blocks of protein and participate in essential pathways that influence tissue repair, cellular function and day to day vitality

In other words, you get B12 at the same rate you use it
