US$ 22.05
alternating day b12 injection How Quickly Does a Work? Timeline and Expectations – Bolt Pharmacy Seeing Red: Do B12 Injections
Description
Using this compound as a marker of cobalamin deficiency, we have been able to demonstrate that cats and dogs with very low serum cobalamin do indeed have a significant tissue-level cobalamin deficiency (Figure 2)

Its possible to have "normal" levels on this test but still have a functional deficiency where your body can't actually use the B12 it has
Optimal B12 absorption depends on selecting the right injection site

Published 2021 Feb 4

5-minute vitamin injections
Product details Vitamin B12 is one of the most important vitamins your body needs to make new cells each day