Ultimate Vitamin B12 1000mcg Methylcobalamin Sublingual Tablet is a higher potency, sublingual tablet providing 1000 mcg of the bioactive form of vitamin B12 to help prevent and correct vitamin B12 deficiency. Vitamin B12 is well absorbed as a sublingual (under the tongue) tablet and acts quickly to restore vitamin B12 levels in the body. It helps with the proper functioning of the brain and nerves as well as the production of red blood cells.