The active substance D-α-tocopherol-polyethylene glycol 1000 succinate (tocofersolan) is a pro-drug; the active metabolite is D-α-tocopherol. At low concentrations, tocofersolan forms micelles which enhance absorption of non-polar lipids such as fat-soluble vitamins. The hydrolysis of tocofersolan occurs in the gut lumen. Taken up by cells, the α-tocopherol moiety appears in chylomicrons in the lymph in a manner identical to vitamin E absorbed from the diet. Cellular uptake does not require receptors, binding proteins or metabolic processes and does not occur by pinocytosis. Absorption of deuterated tocofersolan showed a normal pattern in lipoproteins: α-tocopherol peaked first in chylomicrons, then in very low-density lipoproteins (VLDL) and finally in low-density lipoproteins (LDL) and high-density lipoproteins (HDL). Located principally on cell membranes, within mitochondria and microsomes, vitamin E is ubiquitously distributed (red blood cells, brain, muscle, liver, platelets) and fat tissues are its major reservoir. Vitamin E is the principal lipo-soluble antioxidant in the organism. It acts as a free radical chain-breaking molecule, stopping the peroxidation of polyunsaturated fatty acids, and is involved in maintaining the stability and integrity of cell membranes.