Called riboflavin when added as a supplement to most dietary supplements, this vitamin is primarily used to treat and prevent migraines. B2 supplements are typically taken orally or injected. Normal doses of riboflavin are considered well tolerated by the body, and is safe to take as a supplement during pregnancy. It is also essential for cellular respiration, and is found in high concentrations in eggs, green vegetables, milk, and meat. Vitamin B2 was first discovered in 1920 and isolated in 1933, and then synthesized for the first time successfully in 1935. Available as both a generic medication and in over the counter supplements, riboflavin is both inexpensive and essential to a healthy diet. In medicine, it has been used for over three decades in tandem with phototherapy to treat neonatal jaundice in infants. Since the light used in phototherapy breaks down both the toxin bilirubin and the vitamin riboflavin, dietary supplementation is necessary during treatment.