How to Self Inject Vitamin B12 at Home The Sanctuary Wellness Institute 96372 CPT Code: Injection of drug substance under skin or into muscle B12 Vitamin injections Lets do my first B12 injection together This is something Ive been nervous about for a long time, but today I finally did itand it honestly wasnt bad at all. I used the Union Medico needle guide When to use CPT code for B12 injection Medical Coding Guide