Alpha-lipoic acid is an antioxidant compound. Like the antioxidant vitamins, alpha-lipoic acid acts to decrease the damage produced by free radicals. Alpha-lipoic acid is normally present in the mitochondria, the energy-producing parts of the body’s cells.
Alpha-lipoic acid may have relevance to neurologic disorders. Unlike some chemicals, alpha-lipoic acid is able to enter brain tissue by crossing the barrier between the blood stream and the brain (blood–brain barrier). Some studies indicate that it may be helpful for a diabetes-associated form of nerve injury known as polyneuropathy and may be beneficial for other complications of diabetes. Studies of alpha-lipoic acid in other neurologic conditions are currently under way. There is limited information about the safety of alpha-lipoic acid, especially for long-term use.
No published studies have evaluated the effectiveness of alpha-lipoic acid in MS. As with other antioxidant compounds, alpha-lipoic acid may, in theory, be beneficial for MS, but it may also, in theory, activate the immune system and be harmful for MS. Also, alpha-lipoic acid is more expensive than antioxidant vitamins. If antioxidant compounds are taken by people with MS, the most economical approach is to take low doses of vitamins A, C, or E (see preceding).