Overview of “medical skin care”: “Medical skin care” mainly refers to the purchase of appropriate skin care products prescribed by a professionally trained dermatologist to provide patients with targeted and personalized skin care advice, to avoid patients blindly buying skin care products on their own. With the development of society and people’s pursuit of skin beauty, “medical skincare” has gradually become popular. 1, the concept and characteristics of medical cosmetics: medical cosmetics is the main carrier of “medical skincare”, usually referred to as “pharmaceutical products”. Different from ordinary cosmetics, its role between cosmetics and drugs, is a special cosmetic can produce certain therapeutic effects, and topical drugs have some similarity, but does not belong to the drug. It is a special cosmetic product that produces certain therapeutic effects, similar to topical medications, but is not a drug. “Medical cosmetics” can be used for skin discomfort and for skin conditions that are not yet clearly diagnosed. As the popularity of “medical skin care” grows, “cosmeceuticals” are also gaining the trust of doctors. These “cosmeceuticals” include cleansing products, complementary therapeutic products (including sunscreens, eye creams, etc.) with fully disclosed formulations that are free of colors, fragrances, preservatives, and even surfactants; high levels of active ingredients; targeted; and safety proven by medical literature and clinical dermatology tests, and free of recognized allergens. Generally speaking, the active ingredients of cosmeceuticals mainly include antioxidants, growth factors, anti-inflammatory substances, natural plant ingredients, fading agents, lipopolysaccharides and peptides, etc. 2, common types of cosmeceutical products: In recent years, many cosmetic manufacturers of products, gradually added some of the corresponding therapeutic and anti-aging role of ingredients, and the original mainly for sensitive skin and other aspects of some manufacturers, but also gradually launched a comprehensive range of skin care products. At present, the domestic market common living spring water, including Avène, Vézel, Skin Spring, etc., its role focused on moisturizing, antioxidant, slow soothing and calming anti-inflammatory effect, some spring water and calcium ions and other ingredients, with a certain anti-allergic effect, focusing on sensitive skin, such living spring water can be judged as pharmaceutical products. Some manufacturers of skin care products series, that the skin care into basic care, day care and night care, etc., and according to this classification, respectively, launched for different people and skin types of skin care products. And in each care category, its different products include different focuses such as cleansing, moisturizing, hydrating, whitening, improving elasticity, wrinkle removal, sunscreen, and improving pigmentation, etc. Some products contain several active ingredients to make their effects more comprehensive. Depending on the area of the skin, skincare products are also available for wrinkle-prone and pigmentation-prone skin, such as eye creams especially for crow’s feet around the orbital area. In fact, such skin care products may contain some therapeutic ingredients, but also in line with the concept of pharmaceutical products. 3, the main mechanism of action of cosmeceuticals: (1), soothing effect: soothing effect is actually the corresponding anti-inflammatory effect, resulting in local skin inflammatory mediators such as prostaglandins, histamine, etc. to reduce the local redness, burning and other discomfort. The soothing effect of active spring water is its main feature, certain spring water calcium ions and other components, has a certain anti-allergic effect. (2), whitening effect: mainly for the production, transport and destruction of melanin. Hydroquinone was once a commonly used whitening ingredient, which can significantly inhibit the tyrosinase activity of melanocytes, leading to a reduction in melanin production and whitening effect, but due to its potential carcinogenicity and the risk of causing damage to the skin’s appearance, the EU has banned the use of hydroquinone in cosmetics in 2001, and it is also listed as a banned substance in China. Arbutin and tretinoin both inhibit tyrosinase activity and reduce melanin production, and are now widely used. There are also many plant extracts that can inhibit tyrosinase activity to some extent. Another major way to obtain a whitening effect is with sunscreen products, which reduce melanin production by absorbing or reflecting UV rays and avoiding their exposure to the skin. Niacinamide can inhibit the transport of epidermal melanin particles to some extent. (3), wrinkle removal and improvement of skin elasticity: The main point of action is to promote collagen synthesis in fibroblasts to improve local fiber content, increase skin elasticity and improve wrinkles. For example, retinoic acid can improve fine wrinkles by promoting collagen production. Topical retinoids improve skin hydration and degree and epidermal proliferation, accelerate collagen synthesis, and also inhibit matrix metalloproteinases (MMPs) so that their ability to degrade collagen is inhibited. Since vitamin C is necessary in the process of collagen synthesis, some scholars have confirmed that topical vitamin C can effectively protect facial skin, and evidence of increased collagen synthesis can be found in skin biopsy and molecular biology. (4), anti-aging: natural aging of the skin is basically inevitable, but the process of photoaging can be avoided or prevented. The damage caused by light-induced and skin metabolism by free radicals is the main mechanism of photoaging. Some anti-free radical ingredients, such as vitamin E, can play an effective anti-aging role. (5), moisturizing: mainly refers to increase the local skin water content and water degree. Such can simply use spring water to achieve, and skin care products in the water is enough to increase skin water content. Hyaluronic acid commonly used in skin care products also has strong water absorption and has a certain moisturizing effect.