To increase your Vitamin B12 and hemoglobin, you will likely need Vitamin B12 supplements (such as methylcobalamin) and iron supplements (like ferrous sulfate), as both are essential for red blood cell production. Folic acid is also frequently combined with these. For severe B12 deficiencies, a doctor may prescribe B12 injections. However, because excess iron can be harmful, it is crucial to get a blood test first to determine the exact dosage you need. Please consult your doctor for a formal prescription. You can also support your levels by eating B12-rich foods (dairy, eggs, fortified cereals) and iron-rich foods (leafy greens, red meat).