Natural Factors Methylcobalamin B12 provides vitamin B12 in its most bioactive form. This one-per-day sublingual formula supports the normal function of the immune system, energy metabolism, red blood cell formation, and helps maintain good health. Methylcobalamin is readily absorbed and demonstrates exceptional activity immediately upon absorption, unlike cyanocobalamin.Medicinal IngredientsNon-Medicinal IngredientsLactose monohydrate, microcrystalline cellulose, croscarmellose sodium, vegetable grade magnesium stearate (lubricant).Helps form red blood cells, prevent vitamin B12 deficiency, and maintain good health.Methylcobalamin, the active form of B12, demonstrates exceptional activity immediately upon absorption, while other forms such as cyanocobalamin must be converted to methylcobalamin in a two-step process.