why does my arm hurt after b12 injection pain arm after a shot? Possible allergic reaction to B12

Increase Energy Vitamin B12 helps produce red blood cells and prevents fatigue

It was investigated as a candidate obesity therapeutic but did not meet its primary endpoints in clinical trials, and no marketing approval followed

Cell Rep

Flu shots can cause arm swelling due to your body's immune response, but if the swelling worsens or persists, it may signal a more serious issue

Warnings Benzyl Alcohol Patients who have early Leber's disease (LHON) a hereditary disease that causes optic nerve atrophy have been found to suffer severe and swift optic atrophy when treated with vitamin B12

Anecdotal evidence reported an improvement in energy levels