How to Give B12 Injections at Home to Yourself PA Relief Instruction Guide for Intramuscular (IM) Self injection of B12 Methylcobalamin 1mg 5mg How to self inject intramuscular vitamin B12 Overview Guy's and St Thomas' NHS Foundation Trust 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 Best Vitamin B12 Injection Site: Administering B12 Shots