Oligomeric Proanthocyanidins
Oligomeric proanthocyanidins, also known as OPCs, are antioxidant compounds. They are one of the main components in several antioxidant supplements, including pycnogenol and grape seed extract. As noted in the sections on these substances, it is not clear that the antioxidant effects of OPCs are beneficial to people with MS. Furthermore, they are more expensive than antioxidant vitamins.