glycine vs glutathione GSH exists as a tri-amino acid combination of glycine, cysteine, and Glycine: The Smallest Anti-Inflammatory Micronutrient
Description
At our Temecula practice, some vegetarians, vegans, people with Crohns or Celiac disease, and alcohol abusers are susceptible to low B-12 levels because of diet choices or absorption issues in our Temecula office

Atrophic gastritis results, which is a chronic inflammation of the gastric mucosa

doi: 10.1093/jn/133.5.1747S

Thus, this can be a common principle
Large injection volumes can cause localized reactions, particularly stinging or a raised bump at the injection site
