B12 injections are typically administered directly into the muscle, known as intramuscular injection
For those experiencing dizziness, paying attention to hydration before morning injection helps
tells the Mayo Clinic, Low levels of B-12 and other B vitamins such as vitamin B-6 and folate may be linked to depression. Studies may be inconclusive, but at the very least, a holistic and integrated approach to ones health in the form of adequate vitamins and nutrients helps achieve a more balanced biology that certainly wont hurt your overall mood
B12 is especially beneficial for individuals who have difficulty absorbing B12 from food or oral supplements, which can occur due to certain digestive disorders, age-related changes, or specific medical conditions
Bibcode:2005Natur.438...90C
(I know I'm guilty!) One popular method for boosting B12 levels is through methylcobalamin injections