Deficiencies with riboflavin are rare; however, it 
usually occurs with other nutrient deficiencies.  As 
flavin mononucleotide or flavin adenine dinucleotide, 
riboflavin acts as an essential coenzyme in many oxidation-
reduction reactions which involved carbohydrate metabolism.
Deficiency may result in oral, ocular, cutaneous, and 
genital lesions.

     

Symptoms and Signs of Riboflavin Deficiency include:

*Cheilosis: cracking at the corners of the mouth and 
infammation of the mucous membranes in the mouth
*Glossitis: swollen and reddened tongue 
*Corneal Vascularization: reddening, burning, itching of 
the eyes and sensitivity to light
*Seborrheic Dermatitis: unusual dryness and greasy scaling
of the skin
*Nerve tissue damage: associated with depression
*Decreased neurotransmitter production: which may affect 
mental function
*Abnormal growth in infants and children
*Conjunctivitis; inflammation of the muscus and lining of 
the eyes.
*Alopecia: hair loss

  There are some predisposing conditions that lead to a 
riboflavin deficiency.  For example,the inborn error of a 
deficiency of D-glucose-6-phosphate dehydrogenase does not 
allow the body to add a phosphate group onto the riboflavin
moleculle to produce FMN, flavin mononucleotide.  Others 
include beta-thalassemia and kidney dialysis; the use of 
chlorpromazine and antimalarials compete with absorption 
while hyperthyroidism drugs depress the flavokinase enzyme.
High estrogen often elevate and deplete circulating 
riboflavin levels.  Furthermore, a predisposition to a 
riboflavin deficiency may cause by diabetes, malignancy, 
congestive heart failure, alcoholism, chronic stress, and 
trauma.

  Primary deficiency is usually associated with inadequated
consumption of milk and other animalproducts.  Secondary 
deficiencies are very common in chronic diarrheas and 
alcoholism, liver, disease, and postoperative situations in
which nutrient infusions lack supplementary vitamins.