Laser treatment is not recommended for scars that are too large, scars that are infected, or scars that occur in patients with scarred bodies. 1. Scars that are too large or too deep. Laser scar removal is the use of laser heat to promote subcutaneous collagen synthesis and structural rearrangement, so as to achieve the purpose of fading or elimination of scars, due to the wide range of skin lesions, the use of laser treatment is difficult to achieve significant results in a short period of time. 2. People with scarred body. Some people are prone to form scars after trauma due to abnormalities in the physiological function of the skin. This kind of people, when given laser treatment, may lead to scar growth and aggravation. Since there are individual differences in treatment effects, you need to ask your doctor for an interview.