The principle of laser blemish removal is through selective photothermal principle, different wavelengths of light are absorbed by the corresponding pigments, and the pigment particles rapidly expand and break up after absorbing the high energy of laser in an instant, forming smaller fragments, which are removed by phagocytes in the body in the subsequent inflammatory reaction. Thus, the purpose of lightening pigmentation is achieved. Generally speaking, after the laser treatment, there will be some redness, swelling and burning sensation or a small amount of infiltration fluid on the affected area, which is a normal phenomenon and will disappear after about one or two weeks. Afterwards, a scab will be formed and will fall off in about seven to ten days, do not scrape it off with your fingers, but let it fall off by itself. When the scabs fall off, the treatment area will be pink, and you must pay attention to sun protection at this time, and the color will gradually normalize after about a few months. In some cases, the color will return to black after two or three weeks, and most of them will start to fade after the second month to six months. Generally speaking, if you are older and your skin metabolism level is low, there will be recurrence after laser blemish removal, which is related to the skin level metabolism. Although the treatment effect is good, you should pay attention to protection, otherwise it will indeed cause recurrence. After laser treatment, make sure to protect yourself from the sun and avoid spicy and stimulating foods for a week. Excessive laser can cause scars and changes in skin texture. The skin after laser use is somewhat of a wound, and bacterial invasion can lead to infection, so careful care and antibiotic creams are helpful. For extensive laser treatments, such as skin resurfacing and wrinkle removal, pre- and post-operative antibiotic and anti-herpetic medications are also required. Because laser is a high-energy light wave, the user needs to have a comprehensive understanding of the cosmetic problem and a reasonable choice of treatment method in addition to proper use. If you need laser treatment, you should consult a professional plastic surgeon or dermatologist.