how long can you store b12 injections Does It Take Vitamin to Work? Vitamin B12 Injections vs. Supplements:

Your body needs vitamin B12 (cyanocobalamin) to break down fat and carbohydrates for energy, and to make proteins and cells

There are rare occasions where vitamin B12 causes allergic reactions or sensitivity

Vitamin B12 Injections, also known as Methylcobalamin, is an essential nutrient needed for proper digestion and absorption of foods and for normal metabolism of carbohydrates and fat

Your reaction indicates things are shifting in a positive way

Scientists at Metabolic Pharmaceuticals in Australia took that fragment and modified it by adding a tyrosine residue to the front (N-terminus)

doi:10.2174/157340313805076322