Laser permanent hair removal uses selective photothermolysis, which can penetrate the skin directly to the root of the hair follicle, causing irreversible damage to the structure of the hair follicle, thus achieving the effect of inhibiting hair regeneration. However, it may also produce certain side effects, including the following: 1. redness of the hair removal area; 2. some patients may show follicular edema, the skin shows a small wind-like performance; 3. if the laser energy is too high or repeated treatment, the hair removal area may blister, or even crust, scar; 4. because the hair follicle and sebaceous glands are close to each other, so hair removal may affect the sebaceous glands, resulting in hair removal after treatment The oiliness of the area is reduced and the skin is slightly less moisturized. Because the penetration depth of the laser is limited, it can only reach the skin layer and is not harmful to other tissues and structures of the skin, including sensation or texture. Occasional discomfort can accompany the treatment process, but it is not a permanent side effect or harm, and the discomfort can be improved quickly. Patients are advised to perform local cooling after hair removal to reduce local discomfort reactions. If you find that the redness of the skin persists after hair removal, or even blisters appear, you should go to the hospital promptly and be treated by a doctor. If there is only slight local redness and follicular edema, most patients can disappear in 1-2 hours after treatment.