where to do a b12 injection Injections at Home - Safety Guide for Self-Administration B12 Injection Dosage and Frequency:
Description
They are used when oral iron supplements are ineffective or unpalatable, such as severe iron deficiency, malabsorption problems, or gastrointestinal diseases that prevent proper oral iron absorption

doi: 10.26355/eurrev_201811_16247

Piglets: 1 ml intramuscular, 3 days after birth

This suggests a metabolic imbalance
