side effect of b12 injection Shots at Home: How, Where & How Often to Inject Yourself Another question that filled my

Clinical indications include deficiency due to inadequate diet or malabsorption, drug-induced deficiency (for example, from long-term isoniazid or oral contraceptives), and certain inborn errors of metabolism (such as pyridoxine-dependent seizures or sideroblastic anemia)

Vitamin B12 for hair, skin, and nails If you have a very low level of B12, you may be prone to hyperpigmentation (dark spots) on your skin, vitiligo (light patches on your skin), mouth ulcers, eczema, and acne

Being water based I don't think b12 requires a large needle like some people like to use

High doses of B12, often used to treat deficiencies, may cause side effects such as headaches, nausea, diarrhea, fatigue or weakness, and tingling in the hands and feet