How Often Can You Get Vitamin B12 Injections? 7 Facts 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 Vitamin B12 Injections for Aging and Longevity InVita Wellness Vitamin B12: How Frequently Should I Get It? URBAN Medical Fishersville, VA and Gilbert, AZ