Vitamin B₂ deficiency may cause symptoms and manifestations such as stomatitis, labial inflammation, and lingual inflammation, etc. If the above mentioned uncomfortable symptoms occur, it is recommended to go to the hospital in time for medical consultation, and standardized treatment under the guidance of the doctor. 1. Keratitis: usually manifested as bilateral erosion of the corners of the mouth. Sometimes transverse fissure grooves can be seen, and the inflammation can extend to the mucosa and skin for about 1cm. Later ulceration will form yellow scabs on the surface. People open their mouths, speak and eat will be affected. 2. Lipitis: specifically manifested as redness, swelling and dryness of the lips and mouth, accompanied by peeling, pain and burning sensation. 3. Tongue inflammation: Early tongue can appear dry feeling, burning sensation and tingling, later the tongue is bright red and swollen, some patients can see cracks or ulcers on the tongue surface.