Blue light usually does not cause direct harm to the skin, some people in the process of using blue light irradiation, skin allergies may occur, skin redness, rash and other manifestations, generally stop using will recover on its own. 1. Blue light irradiation is a commonly used treatment for neonatal pathologic jaundice, acne, blue light almost does not cause damage to the skin, but may cause damage to the retina, so you need to wear a good eye mask in the treatment process. 2. Some people may have skin allergy when receiving blue light treatment, which is mainly manifested as localized redness of the skin, and may also appear as a rash. After stopping the use of blue light irradiation, the symptoms can be improved, and there is no need for too much treatment in general. It is recommended that patients under the operation of a professional doctor for blue light irradiation treatment to avoid adverse reactions.