Riboflavin (vitamin B2) is part of the vitamin B group. Riboflavin 5’-phosphate is the precursor of two coenzymes, flavin adenine dinucleotide and flavin mononucleotide, which catalyze oxidation/reduction reactions involved in a number of metabolic pathways. FAD and riboflavin phosphate in foods are hydrolyzed in the intestinal lumen by nucleotide diphosphatase and a variety of nonspecific phosphatases to yield free riboflavin, which is absorbed in the upper small intestines by a sodium-dependent saturable mechanism. Riboflavin has been used in several clinical and therapeutic situations. For over 30 years, riboflavin supplements have been used as part of the phototherapy treatment of neonatal jaundice. Corneal ectasia is a progressive thinning of the cornea; the most common form of this condition is keratoconus. Collagen cross-linking is a non-surgical treatment intended to slow progression of corneal ectasia by strengthening corneal tissue. The standard protocol calls for application directly to the eye of a 0.1% riboflavin solution for 30 minutes followed by 30 minutes of ultraviolet-A irradiation with a wavelength of 370 nm and power of 3 mW/cm2. Under the conditions used for corneal collagen cross-linking, riboflavin 5‘-phosphate functions as a photo enhancer and generates singlet oxygen which is responsible for the cross-linking.

Flavin mononucleotide, or riboflavin-5′-phosphate, is a biomolecule produced from riboflavin by the enzyme riboflavin kinase and functions as prosthetic group of various oxidoreductases including NADH dehydrogenase as well as cofactor in biological blue-light photo receptors. Riboflavin (Vitamin B 2) (as riboflavin 5-phosphate sodium) is an ingredient of the FDA approved composition Infuvite Adult, indicated as a daily multivitamin maintenance supplement for adults and children aged 11 and older receiving parenteral nutrition. Infuvite Adult is also indicated in other situations where administration by the intravenous route is required. Such situations include surgery, extensive burns, fractures and other trauma, severe infectious diseases, and comatose states, which may provoke a “stress” situation with profound alterations in the body’s metabolic demands and consequent tissue depletion of nutrients. Flavin mononucleotide is also a component of Cytoflavin, used for the treatment of consequences of cerebral infarction, for the treatment of atherosclerosis, encephalopathy, neurasthenia. Cytoflavin is marketed in Russian Federation.