Medicine & USMLE

Vitamin B2 (Riboflavin)

  1. Vitamin B1 (Thiamine) Biochemistry
  2. Vitamin B1 (Thiamine) Deficiency
  3. Vitamin B2 (Riboflavin)
  4. Vitamin B3 (Niacin) Biochemistry
  5. Vitamin B3 (Niacin) Deficiency and Excess
  6. Hartnup Disease
  7. Vitamin B5 (Pantothenic Acid)
  8. Vitamin B6 (Pyridoxine)
  9. Vitamin B7 (Biotin)
  10. Vitamin B9 (Folate)
  11. Vitamin B12 (Cobalamin) Biochemistry
  12. Vitamins B9 and B12 Deficiencies
  13. Vitamin A (Retinol) Biochemistry
  14. Vitamin A (Retinol) Deficiency and Excess
  15. Vitamin C (Ascorbic Acid) Biochemistry
  16. Vitamin C (Ascorbic Acid) Deficiency and Excess
  17. Vitamin D Biochemistry
  18. Vitamin D Deficiency and Excess
  19. Vitamin E (Tocopherol/Tocotrienol)
  20. Vitamin K Biochemistry
  21. Vitamin K Deficiency
  22. Zinc
  23. Kwashiorkor and Marasmus


Vitamin B2 (Riboflavin) is a water-soluble vitamin which serves an important role as a precursor for the flavin coenzymes, including flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD). These flavins serve as cofactors in a number of redox reactions. One of the major enzymes requiring flavins (FAD+) as a cofactor is succinate dehydrogenase, which plays major roles in the Citric Acid Cycle and electron transport chain. In patients with riboflavin deficiency, cheilosis and corneal vascularization are characteristic findings.

Key Points

  • Vitamin B2 (Riboflavin)
    • Component of flavins (FAD, FMN)
      • used in electron transport chain and as cofactors in redox reactions:
        • Succinate dehydrogenase
          • Converts succinate to fumarate in TCA cycle
  • Deficiency
    • Cheilosis
      • inflammation of lips; scaling and fissures at the corners of the mouth
      • Also glossitis and stomatitis
    • Corneal vascularization

Find Riboflavin and other Vitamins among Pixorize's visual mnemonics for the USMLE Step 1 and NBME shelf exams.