Ever wonder why B12 shots are red? Here's the scoop! , B12 injections naturally have a deep red color due to the presence of the cobalt corrin complex, a key component of its molecular structure. Vitamin B12 Injection site red and itchy : r AskDocs Fun Fact Friday! Ever wondered Why is my B12 injection red? All B12s are cobalamins they have a cobalt atom at the center of a special ring shaped molecule called Vitamin B12 Inejctions at Skin2Soul MedSpa & Regenerative Medicine B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics