No human trial has established a best time, meal rule, or split schedule
Several factors influence the choice of needle and syringe: Type of injection : Intramuscular (IM) or subcutaneous (SC) Gauge of the needle : Diameter of the needle Length of the needle : Determines the depth of injection Volume of the syringe : Determines the amount of B12 to be injected 3
Your doctor will give you the right dosage of vitamin B12 supplement, especially if you will inject it
References: Mark Heffernan, Roger J
Always share your full health history with your provider
In general, serious side effects from B12 injections are rare but in some cases, people may experience a few mild ones including pain, redness, or bruising at the site of injection