Photorejuvenation applies specific intense pulsed light, which is directly irradiated on the skin surface and can penetrate to the deeper layers of the skin, selectively acting on skin pigments or blood vessels, destroying pigments and closing abnormal red blood vessels, effectively treating skin surface imperfections, improving skin elasticity, color and delicacy, and maximally satisfying consumers’ pursuit of a high-quality image. But photorejuvenation also has the following side effects: 1. Burning skin: when photorejuvenation treatment is carried out, if the photon energy is too large, it will burn the skin and play a counterproductive role; 2. Skin sensitivity: after treatment, the skin of lovers tends to become abnormally sensitive, with itching, redness and peeling; 3. Melanin deposition: incorrect photorejuvenation treatment may lead to skin cell damage, and the skin is unable to carry out 4. Damage to the stratum corneum: When the stratum corneum of human skin is damaged, the skin will lose its protective barrier, nutrient loss will be accelerated, the skin will become unbalanced and aging will be accelerated. 5. Post-operative rebound: There are certain risks associated with photorejuvenation, such as rebound after spot removal, and the area of pigmentation will be larger than the original. 6. scar growth.