Thats because vitamin B12 is bound to protein and can only be released by digestive substances in the stomach (hydrochloric acid and gastric protease) to be absorbed
Each time, vary the injection site (alternate legs, for instance) to prevent soreness or muscle irritation
How often should I receive Vitamin B12 injections
The methylcobalamin form in particular shows nerve-repairing properties, and has been shown to reduce homocysteine levels, treat peripheral neuropathy, ALS, multiple sclerosis, Alzheimer, Bells palsy, and other neurological disorders
Nonetheless, this work has identified novel findings that support future studies to determine whether microbiome changes are contingent upon the combination of both NNMTi and LD switch and mediated through direct NNMTi-driven mechanisms or through indirect mechanisms such as weight or fat loss 8,13