injection sites for b12 Instruction Guide Intramuscular (IM) Self-injection of Methylcobalamin 1mg/5mg B12 Injection Dosage and Frequency:

Mechanistic link between vitamin B12 and Alzheimers disease

Route Topical / transdermal Published Dose Context Marketed by some clinics and compounders, but no published human exposure data was identified in FDA's December 2024 evaluation

Symptoms like nerve damage or brain fog can be helped by quick action

Theoretical and route-specific risks FDA's 2024 review specifically flagged that no published human exposure data exists for the subcutaneous, transdermal, or intranasal routes that compounding pharmacies have offered

During prolonged exercise or heavy sweating, replacing electrolytes may also be beneficial