Fumaric Acid-d2 is the isotope labelled analog of Fumaric Acid. Fumaric acid is a compound that occurs in many plants. It is essential to vegetable and tissue respiration and also used as an antioxidant. Fumaric acid is also a metabolite of Dimethyl Fumarate (D464965), a compound used as a treatment for the relapsing forms of multiple sclerosis and psoriasis.