where do you give b12 injection Injections at Home - Safety Guide for Self-Administration Treating Severe Vitamin B12 Deficiency
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In fact, most patients are pleased with the effects of their treatment, which last for six to twelve months following the initial injection

Enhanced Cognitive Function: Regular B12 supplementation may help prevent cognitive decline

Nature 585 , 261267 (2020)

It is administered by a doctor or nurse through injection, typically in a muscle or vein, as the situation dictates
While results from in vitro studies suggest that vitamin B-12 may increase alpha-diversity and shift gut microbiome composition (beta-diversity), findings from animal studies and observational human studies were heterogeneous

What are the risks of B12 injections for weight loss
