b12 self injections video How to self-inject intramuscular vitamin - Overview How to Self-Inject Vitamin B12
Description
Olympia offers compounded Vitamin B12 in the form of methylcobalamin, hydroxocobalamin, and cyanocobalamin injections

The safety data is excellent

Wainwright P, Narayanan S, Cook P Clinical biochemistry 2015

These are very effective at raising blood levels of B12 and preventing/reversing a deficiency
This deficiency can cause a range of health problems, from fatigue to nerve damage