Acne is a chronic inflammatory lesion of the hair follicles and sebaceous glands related to sebum metabolism, and is commonly referred to as “acne” because it occurs during puberty. The onset of acne is related to the metabolism of sebum. As long as there is life, there will be sebum metabolism, so there will be the possibility of acne, but there are different incidences at different ages. High prevalence during adolescent development. Whiteheads and blackheads, papules, pustules, nodules and cysts appear mainly on the face, and in some cases, scars are even formed. Patients often experience psychiatric symptoms such as anxiety, depression, low self-esteem, and social inhibition. The main cause of acne is the increased secretion of sebum by the sebaceous glands. During pubertal development, androgens can stimulate increased secretion of sebaceous glands; well-developed gonads and sebaceous glands, hypertrophy and hyperplasia of glands, and increased secretion. The first reason for this is that the incidence of puberty is higher, which is the reason for the “acne”. The second reason is that the hair follicle is blocked, the hair follicle is a pipeline system, the hair follicle mouth, the lumen of the problem, will occur inflammation. This is the common white particles that grow on the face, called whitehead pimples or milia. The third reason is bacterial infection. In addition to blocking the hair follicle duct system, it is also related to the increase and aggregation of microorganisms. On the surface of the human skin, there are some resident bacteria in the skin and hair follicles, which are not pathogenic in themselves, but these microorganisms will cause problems in the process of acne formation under specific circumstances, especially sweat, sebum is a substance containing lipids, and when more sebum is secreted and the sebum is thick, together with When the dust from environmental pollution and the shed keratinized cells mix together, they clog the hair follicle, and the change in the environment of the hair follicle at this time is a lack of oxygen. There is a bacterium called Propionibacterium acnes, which is very sensitive to oxygen deprivation, so when it is deprived of oxygen, it increases in number and size, and immediately gathers together, and when it multiplies strongly, it penetrates into the skin ducts, thus producing papules, pustules, nodules and cysts. Therefore, after the growth of these things, the pores become enlarged and dilated because the sebaceous glands block the hair follicles for a long time, and scars may occur, both in the form of hyperplastic scars and depressed scars. The fourth cause is genetic, basically about 60% of patients have a family history. The fifth reason is related to drugs, especially drugs containing iodine and bromine, as well as long-term hormone use, which can cause acne. After the capillaries are dilated, the permeability of the blood vessels is increased, and some large molecules inside the blood vessels tend to leak out, so that allergy symptoms and infection and inflammation can easily occur. The sixth reason is environmental factors, mainly including the natural and social environment. Pollution of the atmosphere, changes in dietary structure, increased dust, hormone abuse, and the accelerated pace of life are all triggers for the occurrence of acne, and it is worth mentioning the mental factor, which is very important. The treatment of acne includes the treatment of acne lesions and the treatment of the patient’s psychological problems. Mild acne: topical retinoic acid or benzoyl peroxide or topical antibiotics. Moderate acne: Oral antibiotics and treatment with anti-androgens in addition to topical medications. Severe acne: Oral isotretinoin with topical medication and treatment with hormones. Be careful not to use topical antibiotics alone. Topical antibiotics need to be combined with retinoids or benzoyl peroxide. Topical medications are not applied only to the affected area, but to the entire onset area; not applied for a short period of time, but for a long period of time; used more at the beginning and later changed to maintenance; avoid local irritating effects. Common side effects of topical medications: erythema, tingling/burning, dryness/flaking, irritant dermatitis. Other treatments include: corticosteroid intracapsular injections, acne drainage, phototherapy (Clearlight), treatment of scarring (gelatin injections, autologous fat grafting, ring drilling, grinding, laser grinding, chemical peels).