Melanin under the nose may have the following clinical causes. The first is ultraviolet radiation, long-term exposure to ultraviolet radiation may lead to pigment changes on the surface of the skin and the formation of melanin. The second is the formation of lipid peroxide, this harmful substance will cause damage to the dermis easily form melanin. The third is irregular life, patients often partial diet, lack of sleep, more stress, will also increase the formation of melanin, some patients such as endocrine disorders and other triggers will also appear. For this situation, it is recommended that patients: 1, avoid ultraviolet radiation; 2, try to avoid often stay up late, try to avoid often eat spicy stimulation, to eat more vitamins, such as vitamin C, vitamin E, with improved melanin nutritional medicine, can prevent and restore the effectiveness of melanin. Patients like this, usually pay attention to keep the stool, urine smooth, usually do not eat greasy, spicy, stimulating, high-fat food. If the local symptoms are heavy, you can go to the dermatology department, ear, nose and throat examination, of course, if individual patients suspect that melanin has some other bad changes, to go to the hospital for examination as soon as possible.