The progression phase of vitiligo, also known as its development phase, is characterized by the enlarging and whitening of the skin patches. This phase primarily signifies that the patches are expanding and becoming more pronounced in color. Vitiligo is related to factors such as reduced immunity, genetic heritage, copper deficiency in the body, or local injuries. Through proper treatment, the progression phase can gradually shift into a recovery phase, where melanin increasingly covers the white patches. Some patients may enter a stationary phase where neither medication nor lack of treatment changes the condition of the vitiligo; typically, if there’s no change for over a year, it enters this stationary phase. If it is determined that the vitiligo is in the progression phase, prompt treatment is crucial to prevent the condition from worsening, which could make treatment more difficult.