How Often Should You Get Vitamin B12 Injections? How Often Can You Get Vitamin B12 Injections? 7 Facts If you have a low vitamin B12 level, injections can go a long way toward improving your health and well being. But if your B12 level is normal, don't fall for claims that What are Vitamin B12 injections Vitamin B12 injections are used to quickly raise your B12 levels when they're low or when your body can't absorb it properly from food or tablets. What Optimal Vitamin B12 Dosage and Treating Deficiency Best Vitamin B12 Injection Sites: Where to Inject B12 PA Relief