how to dose b12 injections Vitamin Injection Dosage Best Vitamin B12 Injection Sites:

[9] Patients should be advised to contact their healthcare provider if they experience any severe or persistent side effects, such as difficulty breathing, chest tightness, severe rash, or dizziness

Cells characterized by rapid division (epithelial cells, bone marrow, myeloid cells) appear to have the greatest requirement for cyanocobalamin

However, if you experience any persistent or severe reactions, such as swelling, difficulty breathing, or other concerning symptoms, its important to contact your healthcare provider immediately

"Prevalence of folate and vitamin B12 deficiency in Mexican children aged 1 to 6 years in a population-based survey"

For repletion of a confirmed deficiency, I use higher doses, typically 1000 to 2000 mcg per day