Several factors can lead to elevated B12 levels, including: Over-supplementation: The excessive intake of vitamin B12 through high-dose oral supplements or repeated intramuscular injections can raise blood levels of B12 temporarily 6
Eur J Pharmacol 727: 7579
The mechanisms differ significantly
Some people may experience mild side effects such as soreness, redness, swelling, or tenderness at the injection site
A 500mcg dose would be a 25-unit draw
In this study, significant positive correlations were observed between tryptophan, tyrosine, and xanthine abundances in the EWAT and the relative abundance of Parasutterella in the cecal microbiome (Supplementary Table S5, outliers removed)