No bad effects were reported
Within the Vitamin B complex, there are several members, including Vitamin B1 (thiamine), Vitamin B2 (riboflavin), Vitamin B3 (niacin), Vitamin B5 (pantothenic acid), Vitamin B6 (pyridoxine), Vitamin B7 (biotin), Vitamin B9 (folate), and notably, vitamin B12 (cobalamin)
Deficiency Those most at risk for developing a vitamin B-12 deficiency are vegetarians -- because the vitamin is found in dairy and meat -- and individuals with absorption problems presented by weight-loss surgery, Crohn's disease and celiac disease
The duration varies based on the deficiency cause, symptom severity, and patient response
Where to Get Vitamin B12 Injections You can receive B12 injections at many medical and wellness clinics