what syringe do you use for b12 injections vitamin injection needle size Choosing the Right Needle and for B12 Injections: A Complete size needle to – Where Should Vitamin B12 Be

Always good to have a reason I have also had this happen when my folate was low , it may be worth you getting it checked I had self inject my B12 every 4 weeks for the last 20+ (cannot really remember how long accurately), and 2 months ago got a similar 'electric shock tingling' all over my body - head, face, arms, hands, legs, feet etc within a couple of minutes of injecting, which lasted about 3 seconds or so

PMID 15883631

He also felt low energy when dieting and would rebound into overeating

The medical evaluation ensures the injection is appropriate for you and minimizes risk

Prevention of premature aging : It helps protect against oxidative stress and reduce the impact of free radicals on cells