Obesity lines are clinically known as expansion lines. When they appear in the early stages, they can be applied with localized retinoic acid preparations as prescribed by the doctor, but the effect of medication is limited and cannot be completely eliminated. 1. Expansion lines are caused by the dermal destruction under the action of excessive stretching, and the linear atrophic depression appears on the skin. Mostly occur in obese people, postpartum women and other people, so commonly known as obesity lines or stretch marks. Expansion lines usually do not affect the health of the body, located in the exposed parts of the skin can affect the aesthetic. 2. At the early stage of the appearance of swelling lines, you can use retinoic acid preparations such as retinoic acid ointment, tazarotene, etc.. It can promote keratin generation and have a certain lightening effect on atrophic lines, but it can’t be completely eliminated. Vitamin A acid preparations can cause local scaling, itching, burning sensation and other side effects, the specific use of drugs is recommended to follow the doctor’s instructions. 3. For patients who are not well treated with medication, laser treatment can be considered. Peeling and non-peeling fractional lasers can be used to treat swelling lines, and the effect is good. If swelling lines appear, it is recommended to go to the hospital in time, under the guidance of the doctor to carry out regular treatment as soon as possible.