The way to take vitamin B₂, as directed, is by mouth (with water), and the dosage is (5 to 10) milligrams three times a day. Vitamin B₂ tablets, usually 5 mg a tablet. If you are treating vitamin B₂ deficiency in adults, take one to two tablets by mouth each time, three times a day. After a week or so of taking the tablets, just switch to taking 1 tablet a day. If you are treating vitamin B₂ deficiency in children 12 years of age or older, the directions are: take 1 tablet at a time, 3 times a day. It is a component of the cofactor of flavoenzymes in the body (flavoenzymes play the role of hydrogen delivery in biological redox), and when it is deficient, it affects the biological oxidation of the body and makes the metabolism impaired. Its lesions are mostly manifested as inflammation of the mouth, eyes and external genital areas, such as stomatitis, labial inflammation, lingual inflammation, ocular conjunctivitis and scrotal inflammation, etc. Therefore, this product can be used for the prevention and treatment of the above diseases. When taking vitamin B₂ on an empty stomach, the absorption is not as good as when taking it with food, so it is better to take it during or immediately after eating. It should not be combined with metoclopramide. Urine is yellowish green after taking. It is forbidden for those who are allergic to this product. The dietary habits of our country can easily lead to vitamin B₂ deficiency. In addition to taking vitamin B₂ tablets, it is more important to eat more foods rich in vitamin B₂ in daily diet, such as: animal offal, egg yolk, various vegetables and so on.