What we colloquially refer to as acne actually has another name in the medical field – acne. What are the factors that create acne? Increased androgen levels, excessive sebum secretion, abnormal keratinization of the sebaceous ducts of the hair follicles, and bacterial infections in the hair follicles. Many patients believe that high skin oil secretion is the root cause of acne, so adequate cleansing of facial oil is the main means of treating acne. Oil secretion is one of the causes of acne, and if you do not clean your face well in time. It will lead to excessive facial oil accumulation, but over-cleaning is also detrimental to the skin, and artificially drying the skin will stimulate the skin to produce more oil. Acne patients commonly have high skin oil secretion. Some studies show that there is no significant difference between the skin water content of acne patients and healthy skin, but clinically we often encounter acne patients with dry, tight and flaky skin. After excluding other potential skin diseases such as seborrheic dermatitis and eczema, we consider that their skin barrier function is damaged, resulting in epidermal water loss. The skin barrier is mainly composed of the stratum corneum, structural lipids and the dermal lipid membrane, the first two of which are similar in structure to a brick wall. They are important components of the skin barrier, while the skin lipid membrane is the outermost defense of the skin barrier. The common factors that affect the skin barrier function in life include physical damage, chemical damage (e.g. cleansing products that remove intercellular lipids from keratinocytes), topical medications (e.g. glucocorticoids, salicylic acid) and bad lifestyle habits (use of overly alkaline soaps). Acne patients themselves have a compromised skin barrier, so they should avoid over-the-counter medications that can potentially cause excessive skin dryness, such as overly cleansing alkaline antibacterial soaps and granular abrasive scrubs, which tend to make the skin barrier more severely damaged and lead to more sensitive skin. While it is important for acne patients to scrub, it is even more important to protect the skin barrier function after moderate cleansing. Therefore, acne patients should choose the right cleansing products and skin care products according to their skin type and their doctor’s recommendations. In addition to proper cleansing, the use of oil-controlling and moisturizing medical skin care products is also a very important part of the process.