Laser hair removal actually uses a selective photothermal reaction, relying on the melanin of hair follicles. It selectively absorbs the energy in the laser to produce high heat, and then kills the hair follicle stem cells, so that hair can no longer grow in the future. Therefore, laser hair removal is permanent. If its bad effect is that it is unlikely to grow hair in this part in the future. If you want to have hair, you may need to do hair transplantation. In addition, in the process of treatment, because it will produce high heat, the pain in treatment is inevitable. Although it has been treated with advanced freezing point depilation, there will still be some pain, which may be the bad consequence of laser depilation. But the pain lasts for a very short time. Basically, it doesn’t hurt much after depilation. In addition, there may be slight edema at the depilation site. It is possible that some people with heavy hair follicle reaction may have small papules near the hair root, which can recover soon. In general, laser hair removal has no permanent complications or permanent harm, because the penetration depth of laser is limited, and it is a selective treatment scheme, which is basically harmless to other parts of the skin. Therefore, laser hair removal is a very safe treatment, which will not break or damage, and will not affect bathing and life.