use insulin syringe to give b12 injections How Inject Using a How to Inject Insulin in
Description
Efficacy and safety of intranasal peptide YY3-36 for weight reduction in obese adults

B-12 for Nerve Health Low B-12 levels can increase the risk of nerve damage over time

If you want to practice inserting a needle before administering fluids to your dog, try performing the same motion on an orange or banana

The use of DSM for the local infiltration of nerve roots is an emerging method to achieve the aforementioned safety improvements
So normal people don't really "store" it but most is not lost