This is a topical medicine, mainly for the treatment of vitiligo, the usual usage of this topical medicine is to apply to the affected area, rubbing medicine 30min after to local sunbathing, or ultraviolet radiation 15-30min, this is the condition needed for this drug to play its efficacy, is to be sure to carry out light. Fish, shrimp, wine, green beans, tomatoes and other related foods should also be avoided during the medication period to avoid affecting the efficacy. The affected area should be exposed to the sun or black light frequently during the use period to keep the affected skin pink in color.