Self injecting vitamin B12. Quick and painless jabs after a B12 by Dr Caroline Palmer Medium Red liquid (vitamin B12) in a disposable syringe with a needle and in a glass ampoule on a white background. Lots of empty space Stock Photo Alamy Amazon.com: Ulove Prs 12 Pack 1ml Industrial Syringes with 25Ga 1 Inch Needle, Plastic Disposable Syringe and needle for Scientific Labs, Liquids Refilling and Measuring : Industrial & Scientific Vitamin B12 Injections: What You Need To Know Is It Okay To Use A B12 Injection With Insulin Syringes? How to Give a B12 Injection: Step By Step Instructions